Multidimensionality of Sustainable Public Procurement (SPP)—Exploring Concepts and Effects in Sub-Saharan Africa and Europe

: Strategic objectives in public procurement, such as environmental or social considerations, are being increasingly referred to under the umbrella term of sustainable public procurement (SPP). The concept of sustainability is intrinsically multidimensional, encompassing environmental, social, and economic aspects. However, the existing literature on SPP highlights the generalization that the regulation and practices of public procurement are biased toward the environmental dimension. There is conflicting evidence from countries in Sub-Saharan Africa (SSA) that calls for further investigation. Analyzing how SPP is actually constituted in SSA and contrasting it with the situation in the European Union (EU), as a spotlight on the Global South and North, contributes to a better understanding of sustainability in public procurement. The comparative analysis will help with understanding processes related to the integration or disintegration of sustainability dimensions in SPP. Our results indicate a contrary orientation on the environmental and the social dimensions in the EU and SSA. Although there is no sign of a comprehensive integration of all dimensions in SPP, there are developments toward the integration of the ‘missing’ dimension in the respective regional setting. Thus, at the moment, achieving a multidimensional implementation of SPP appears to be more a matter of expanding SPP practices of the ‘missing’ dimension than of pushing for integrated concepts. as one on the Global North, to answer the questions regarding how the multidimensionality of sustainability is being integrated into SPP regulation and practices, how this is based on national or regional political interests and discourses, and what the current tendencies are toward a multidimensional conception and practices of SPP. study shows that there are different biases in different parts of the world within the concept of SPP. We focus on the regions of the EU and SSA, as they illustrate contrasting biases toward environmental and social considerations respectively when compared.


Introduction: How Multidimensional Is Sustainability in Public Procurement?
At the international level, the Brundtland Report highlighted in 1987 the three-dimensional aspect of sustainability [1]. Today, the extension of sustainability beyond environmental aspects, namely by integrating social and the economic dimensions, has become the common ground. It has also entered the private sector as the 'triple bottom line'-a term introduced by Elkington, who states that business success depends not only on profitability but also on environmental quality and social justice [2] (p. 70). However, an integrated approach to the different dimensions-the environmental, the social, and the economic-is a rather new phenomenon, as there used to be a clear separation in the pre-sustainability discourse between environmental and socio-economic issues, especially in the Global North [3] (p. 38). All three dimensions are also mirrored in the 17 Sustainable Development Goals (SDGs) of the United Nation's Agenda 2030, and efforts to integrate them fully within the notion of sustainable development have increased considerably in recent years. The threedimensional notion of sustainable development needs to be continuously analyzed, and if necessary to be restyled in order to not become a mere mantra [4]. The three dimensions of sustainability have also filtered into the discourse on public procurement, and can be subsumed under the umbrella term of sustainable public procurement (SPP). This describes the use of public procurement for the promotion of a more sustainable economy [5]. In the procurement sector, as in other sectors, the three dimensions of sustainability are being considered differently, depending on the national and regional context. Significant differences exist between public entities within the same country to the extent that a coherent understanding and implementation of all three dimensions of sustainability is often not visible in government policies and practices. This is primarily due to the different foci and interests of the implementing actors and the societal goals they aspire to reach through public procurement. Existing concepts of SPP and their practical applications vary between public entities and are dependent on their respective national context. As a result, SPP varies tremendously, both horizontally, with regard to the sustainability dimensions covered, and vertically, with regard to the effective range of the aspects integrated into public procurement. Based on this, a two-dimensional classification of SPP can be created. The economic, environmental, and social dimensions of sustainability are aligned on the x-axis, while the spatial scope of the effects of SPP-local, national, and international-are on the y-axis.
Therefore, we analyze and compare the different expressions of SPP in countries in Sub-Saharan Africa (SSA) as a spotlight on the Global South, and EU member states and the regional economic community of the European Union (EU) as one on the Global North, to answer the questions regarding how the multidimensionality of sustainability is being integrated into SPP regulation and practices, how this is based on national or regional political interests and discourses, and what the current tendencies are toward a multidimensional conception and practices of SPP. Our study shows that there are different biases in different parts of the world within the concept of SPP. We focus on the regions of the EU and SSA, as they illustrate contrasting biases toward environmental and social considerations respectively when compared.
The economic dimension of sustainability has always been featured prominently in the Global North, where public procurement policies have long been associated with support for Small and Medium Enterprises (SMEs) and for national companies. Even in liberal countries such as the United States of America (USA), the 'buy America' approach has featured consistently in procurement legislation, and is now emerging assertively in the Global South as well, pushed perhaps also by that same neoliberal agenda that has placed great emphasis on the economic significance of public procurement and has pushed for reforms of the public procurement systems in the south as part of an essential step to development [6]. The other two dimensions of sustainability, namely the social and the environmental, have developed differently in SSA and the EU. In contrast to the widespread impression, the bias is not entirely toward the environmental dimension. However, a divide between the EU and SSA can be observed, with the EU and its member states more prone to focus on environmental standards within the procurement process as part of green public procurement policies. Countries in SSA only more recently embraced green procurement-at times reluctantly and as part of donors' requests, while having longstanding experiences including social considerations in public procurement regulations and practices. A new trend seems to be developing whereby donors financially support the implementation of environmental standards in the procurement reforms of developing countries or insert such standards as part of other soft law instruments linked to procurement under the regulatory framework of development aid or international development organizations, such as for example in Article 16 of the Organisation for Economic Co-operation and Development (OECD) Recommendation on Untying Aid to Least Developed Countries (LDC) and Heavily Indebted and Poor Countries (HIPCs) [7]. The south's environmental choices generally "come with the prerogative of poverty eradication in the here and now: a difficult political trade-off" [8] (p. 147).
When analyzing the situation as regards the social aspects of sustainability, horizontal and vertical differences can be identified: On the horizontal axis, depicting the sustainability dimensions, countries in the Global North as well as in the South have integrated social aspects in their procurement regulations and practices, albeit with differences in terms of how broadly the social dimension is covered. Public entities in SSA have focused more on social and human rights aspects in their procurement, with a predominant inclination for equality and reparation for past injustices, for which the best example is post-apartheid South Africa [9,10] (pp. 381, 11), while actors in the EU have focused on labor rights (including the disability and social security aspects of labour rights) as incorporated in national and international legislation, which was already the case in many countries in Europe before and after the regulation of public procurement by the EU. This divide might also be seen as a continuation of the gap between the more developed and the less developed countries that lies at the origin of sustainable development. As Nico Schrijver argued, "[s]ustainable development as interpreted by the Rio Declaration of Principles represents a balance between the concerns of the industrialised and the poor countries" [4].
The vertical axis refers to where SPP has an effect: domestic, regional, or international. Approaches to social aspects in public procurement in SSA as well as in the EU have a domestic focus in common, where the effects of SPP are targeting, for example, labor rights in the national context. In a rather new development in the Global North, especially in the member countries of the EU and some states in the USA, there are aspirations to extend the effective range of the social dimension beyond national considerations, toward social standards along international value chains. At the same time, a new trend seems to be emerging in the Global South, with a renewed attention to environmental criteria. Yet, these aspirations are often only considered in pilot projects, as noted below. Therefore, the divide between the EU and SSA manifests itself not only in an offset development regarding the legal status of different sustainability dimensions in public procurement, but also in the recent aspirations of countries in the EU along the vertical axis, expanding the effective range of social aspects, and those of countries in SSA that have extended along the horizontal axis to include environmental objectives in public procurement.
The universal pursuit of human and workers' rights in the Global South goes hand in hand with the globalization of the supply chain. Whereas enterprises, including multinational enterprises (MNEs), try to maximize their profits, workers involved at the upstream stage are often exploited, and human rights and labor laws are violated. Moreover, raw materials are often unethically sourced with negative social impacts. One example is 'conflict minerals', where "the profits from these minerals at times directly fund armed groups that are involved in waging civil wars in countries throughout the region, especially in the Democratic Republic of Congo" [11] (p. 148). If these interdependencies have been overlooked for quite a while by actors in the Global North, globalization of the economy has made it an issue of relevance around the world, with important consequences for trade and public procurement, e.g., in relation to fair trade. SPP can contribute to a higher degree of sustainability, including high social standards, along international supply chains.
Comparing approaches to the integration of different dimensions of sustainability in the Global North and South shows that a more particularized analysis is needed. One aspect is that in order to compare different approaches to SPP, one has to integrate the spatial aspect as a vertical dimension into the analysis of public procurement to assess the (intended) effective range of sustainability considerations. By doing so, it is possible to distinguish between effects intended to appear in the national or even the local context where the procurement is carried out (domestic social aspects), and those intended to appear along international supply chains (international social aspects). In the context of the EU, an excessive focus on the trade and competition aspects of public procurement and the need to limit the discretion of procurement officials for fear that these measures could conceal discriminatory intentions have partially constrained SPP in the past. While many social aspects, such as adherence to collective agreements, compliance with external legislation, and regulation and preferential treatment of sheltered workshops, have been and are still possible, other qualitative aspects of the social dimension, such as preferential treatment for marginalized groups and other policies that entail a higher level of discretion for procurement entities are often forbidden (or very reluctantly allowed, only in clearly defined circumstances). Most countries apart from the EU integrate reservations for marginalized groups and other aspects of public procurement that incorporate social aspects beyond labor laws, such as human rights, into regulation and practices, as is the case in many SSA countries such as South Africa, Kenya, Zimbabwe, Namibia, Uganda, and Botswana, as well as in the USA and Canada (see [12]).
Concepts of SPP have their foundation in individual (regional, national, municipal) histories and power relations that are often connected to global, but also national and local discourses on sustainability. This is partly at odds with the normative three-dimensional concept of sustainability, which is based on the idea of strong reciprocity and therefore an interlinkage of the different dimensions. For example, another element of peculiarity in the way that SPP has been implemented can be noted by looking at the way that SPP has been implemented by municipalities. The role that cities have played in pushing forward the debate on SPP, especially within the EU, has often been overlooked, yet our analysis reveals that municipalities have played a fundamental role in pushing forward the boundaries of SPP.
Thus, the global picture of SPP seems patchy (to say the least). Experiences and approaches in the implementation of SPP appear to be still different at the international, national, and local levels. In many countries in SSA, there is insufficient regulation in relation to the environmental aspect of SPP, while in the EU there is still great uncertainty regarding the international social aspects of SPP. National as well as municipal stories of the introduction and implementation of SPP present a variety of different emphases on specific aspects of sustainability.
Finally, it needs to be remembered that academic disciplines, political discourses on international, regional, national, and local levels, as well as discourses within the private sector shape our understanding of SPP, which is by no means uniform, but rather is characterized by a patchwork structure. Apart from the different national starting points of SPP, which lead to a concentration on specific aspects within SPP, the overall compatibility and the potential and limits of synergies between different dimensions has to be questioned and analyzed in order to assess the coherence of SPP in regard to a multidimensional concept of sustainability. This partly theoretical discourse also has implications for the practical implementation of SPP, as answers to these questions might help identify entry points for SPP and ways forward to further and maybe more comprehensively integrate environmental and social considerations into public procurement.
In order to test our hypothesis of a division regarding the difference in the integration of the environmental and social dimensions into public procurement, we gather and compare evidence in the form of regional and national examples.
In Section 2 of this article, we present the methodology used to derive our conclusions. In Section 3, we discuss the aspect of multidimensionality within the concept of sustainability and explore the challenges and opportunities to multidimensionality in SPP. In Section 4, we explore regional and country cases to gather evidence for answering the following two research questions. First, based on the examples of SSA and the EU, how is SPP constituted in regard to its multidimensionality in the Global South and North? Second, is there a trend toward an integration or disintegration of dimensions of sustainability in SPP? This is followed by a conclusion in Section 5.

Methodology
To depict the national and partly regional differences in approaches to SPP between countries from the EU and SSA, and to answer the subsequent research questions, we are using a crossdisciplinary approach, combining methods from legal research with those from political science. Efforts to analyze changes toward a more sustainable society and economy are often based on simulations and models from economics and sociology. Agent-based and network models for answering questions on how to deal with climate change in different fields, from technological innovations over finances to policy measures, are being used increasingly, and are slowly replacing equilibrium models [13] (p. 262). One of the reasons for this shift is the ability of agent-based and network models to depict and predict the complex societal interlinkages at work in the processes of change. For example, Ponta et al. use an agent-based macroeconomic model to analyze sustainable transition in the energy sector [14]. However, when dealing with the transition toward more sustainable public procurement, legal and regulatory questions are at the center of attention, as public procurement is a highly regulated process. To analyze national and regional differences in the multidimensionality of SPP, research methods are needed that integrate the regulatory framework and administrative practices of SPP. For the analysis of the legal framework, we draw on doctrinal research, which is common in legal studies, that "provides a systematic exposition of the rules governing a particular legal category, analyses the relationship between rules, explains areas of difficulty and, perhaps, predicts future developments" [15] (p. 101). At the same time, laws and regulations cannot be analyzed on their own as they are not a reflection of reality but a set of normative aspirations. The attempt of traditional doctrinal research "to explain law solely through the internal evidence offered by judgments and statutes", has long been overcome [16] (p. 71). Our attempt is to widen the scope of materials and data beyond the legal framework, using a comparative method from the field of political science.
By rejecting the idea of a general global bias toward the environmental dimension in SPP, due to our experiences with contrary cases, we conducted a "hypothesis-generating" [17] (p. 691) case study to formulate more realistic hypotheses on the integration of multiple sustainability dimensions into SPP. The country cases selected for our analysis from SSA and the EU are those with profound experiences of regulations and practices of SPP, and therefore present using typical cases [18] (pp. 299f). In the analysis, we identify different orientations toward specific dimensions of sustainability in the SPP efforts of the country cases. Then, we compare the cases regarding the expression of multidimensionality in their SPP regulations and practices.
To do so, we generate data on the orientation of procurement regulations regarding the dimensional foci of sustainability, by analyzing primary materials consisting of legal texts (specific laws, regulations, and directives) and secondary materials, such as policy concepts and action plans by governments, as well as academic literature on the discourses on sustainability, public procurement, and SPP. Secondary materials need to be included in order to understand how the law is implemented in practice. In the end, the framework and its implementation determine the focus of SPP practices. This is done to trace the orientation of SPP in each national case within the legal framework, political statements, and administrative practices. By comparing these typical cases, we are generating the hypotheses described in the introductory section and replacing the global generalization of dimensional biases in SPP with a more detailed account of dimensions of sustainability in SPP in the regional contexts of the EU and SSA.

Interlinking Dimensions: What Are the Opportunities and Challenges for Connecting Different Dimensions of Sustainability in SPP?
The well-known definition of sustainable development laid down by the already mentioned Brundtland Report emphasized the concept of a 'development' that meets "the needs of the present without compromising the ability of future generations to meet their own needs" [1] (p. 36). Meeting these needs meant that economic growth could no longer continue to be considered the highest objective to achieve, regardless of the social and environmental considerations. Therefore, a new idea of development has been shaped on the basis of three pillars (economic, social, and environmental), which sum up the concept of sustainability and are designed as necessarily complementary and interlinked with each other.
Even if positive changes have been realized at different levels (starting from the development of a different mindset and a more environmentally and socially friendly culture), the expression "sustainable development" is very broad and abstract, with many different facets [4] (p. 372) and priorities (which may sometimes contradict or conflict with each other). Moreover, priorities may be pursued potentially at the same time without any clear or well-established hierarchy. This may create confusion and lead to heterogeneous national implementations or even make it more difficult to implement sustainable-oriented policies at a local level.
Recognizing that sustainability has been for quite a long time a buzz word or a "fuzzy concept" [8] (p. 151) "conveying a multitude of meanings that are often divergent to a variety of individuals, professions, interest groups, governmental agencies, political leaders, NGOs [nongovernmental organizations] and grassroots organizations" is not something new [19]. This "ethereal nature" has often been perceived as "a blessing and a curse": whereas it commands a "near universal" cooperation and support, it "eludes any attempt to be prescriptive" [8] (p. 150) or to provide a more homogeneous and coherent meaning. This has led McCloskey to argue that "the emperor [sustainability] has no clothes on", as in the past, sustainability represented a need to share a common high hope (of a more just and green world), whereas nowadays, it represents the more concrete need for "a useable line of thought-an operational reality" going beyond any vagueness and fuzziness [20] (p. 159). Therefore, more than 30 years after the Brundtland Report, there seems to be a growing awareness of the need to "prevent sustainable development from becoming an allencompassing concept, if not a mantra" disconnected from reality [4]. In this sense, it seems that the three-dimensional notion of sustainable development needs to restyle itself or, at least, that "there should be an accurate and continuous reconsideration of what could or could not be part of the concept" on the basis of concrete experiences [4]. More specifically, since the levels of "maturity" and of implementation of the heterogeneous dimensions of SPP are different, it is necessary to reflect on how the three dimensions of sustainability can be strengthened to be kept together, and subsequently inform procurement policies in a multidimensional way both horizontally and vertically. Ultimately, the current fragmentation is unsatisfactory. If environmental protection is a global concern and often appears as prevailing against the implementation of the social pillar, social issues are usually linked to a specific local context and generally have specific national boundaries. For instance, provisions on working conditions or the inclusion of vulnerable workers are mostly specified by national discourses, whereas environmental aspects, such as reducing energy consumption and the emission of greenhouse gases, appear to be more universal. This is also true when integrating sustainable development into public procurement. Here, the complexity increases as the heterogeneous multidimensional nature of sustainability meets the crosssectional nature of public procurement, which crosses different fields such as law, economics, management, and sustainable development. In other words, when adopting a SPP-based approach, public entities have to look beyond the simple price/cost of the purchases and go beyond a mere economic approach. They have to take into account different kinds of social and environmental considerations without overlooking legal and management issues. This requires procurers to have multidisciplinary competences as well as strong and clear political, legal, and institutional frameworks. As to the latter, policymakers need to make an effort to simplify the legal context, since there seems to be an incredibly high number of policies, tools, and legal instruments regulating SPP (an estimated 300) [21][22][23]. This simplification might also contribute to a "common guiding framework enabling public entities to accomplish more easily their day-to-day procurement tasks" [23]. This might allow for a step-by-step introduction of the multitude of dimensions and aspects of SPP.
There are concepts that try to overcome these challenges and try to present an integrated concept of sustainability. Interlinkages between the social and the environmental pillars of sustainability are emphasized in the concept of "climate justice", for example. The concept has been developed to stress that environmental issues are not purely physical but also a rights issue. Climate justice links "human rights and development to achieve a human-centred approach, safeguarding the rights of the most vulnerable and sharing the burdens and benefits of climate change and its resolution equitably and fairly" [24]. In this sense, there are important intergenerational and intragenerational linkages: environmental issues (as a rights issue) concern not only the present generations but also the next generations. However, also beyond the climate justice concept, the question of intergenerational and intragenerational justice is in the nature of the sustainable development concept itself [25]. In other words, generational effects can be in space (intra-) and in time (inter-): the horizontal line between different generations, which coexist at the same time up and down national barriers, crosses the vertical line between the present and the future. Even if some authors criticize the assumption that "present planners can foresee the future ad infinitum" [20] (p. 155), it is important to stress that the same definition of sustainable development, as provided by the Brundtland Report, shows the intergenerational equity in the use of the Earth's natural resources. Under a sustainability-based approach, meeting the present needs does not mean compromising future generations' ability to meet their own needs. Regarding the social dimension, intergenerational equity can be an important part of shaping a desirable future, as we will see in the public procurement practices of South Africa and Kenya. Social aspects beyond the local, national, and international social aspects of justice (as in intragenerational justice) have to be considered. This is achieved in SPP at the national and sometimes the regional level. The exploration of intragenerational justice at the international level has just begun in the economically developed countries of the Global North.
Sustainable development has various facets and is intended to serve different and often conflicting objectives. In the following section, we will analyze how its multidimensionality is being integrated into SPP regulation and practices, and how this is based on national or regional political interests and discourses, as intergenerational and intragenerational priorities can be pursued differently in the regulation and practices of SPP.

SPP in the Global South and North: Different Societal Goals in Public Procurement?
Generalizations about SPP are mostly based on biased conclusions that do not take sufficient account of examples and experiences, especially those from the Global South. As a result of reports and research on SPP, an impression has been gained that there is an overwhelming focus on the environmental dimension in SPP practices. The latest Global Review on Sustainable Public Procurement by the United Nations Environment Programme (UNEP) seems to reveal that, in practice, socioeconomic issues in SPP are clearly subordinate to environmental aspects. A survey of the sustainability issues addressed by national SPP policies among countries worldwide shows that socio-economic issues are addressed less, taking up the bottom half of the distribution, while sustainability issues that deal only with environmental issues are more often included in SPP policies, and therefore make up the top half [26] (p. 16). This distribution continues in the scope of the agencies leading the implementation of SPP policies. In 81% of the cases, "ministries or agencies with environmental responsibilities" oversee SPP policies [26] (p. 17). However, this focus on the environmental dimensions of sustainability in SPP is the result of a fallacy in the collection of data by the UNEP and its insufficient account of experiences from the Global South. Most countries that answered the surveys sent out by the UNEP are in the OECD, and many are from the EU. Only one country from SSA, the Ivory Coast, completed the questionnaire [26] (p. 92). Therefore, the report is strongly biased, as it does not truly present a global picture. Research on SPP from an international perspective tends also to present generalizations for phenomena that present themselves as quite different from a regional or even national perspective. Brammer and Walker conclude, in their generally very insightful study, that "[a]cross regions, environmental aspects of SP [Sustainable Procurement] are relatively established but there is variation in other aspects of SP such as buying from diverse suppliers, supporting human rights and ensuring safe practices in the supply chain" [27] (p. 472). While the second part of their observation can be supported, our research shows that their first assumption has to be contested, as many countries in the Global South, especially in SSA, have only just started to incorporate environmental considerations, while having a longer history of including social considerations in their public procurement. For example, in South Africa, the inclusion of social considerations in procurement aimed at addressing the legacies of colonialism and apartheid is explicitly mandated in the Constitution and has been implemented through an extensive preferential procurement scheme [28]. However, there is as yet no explicit provision for environmental considerations to be generally taken into account in the procurement system at the national level, and only one of the nine provinces has started developing policy in this respect [29]. Brammer and Walker's approach is representative of a widespread Eurocentric view of SPP. Such Eurocentric observations and analysis of public procurement suggests that environmental considerations have been and still are at the center of SPP, while social considerations come to the fore only sparsely.
When a Eurocentric view on SPP is abandoned for a broader more inclusive look into the realities of SPP in diverse country and regional contexts, a different picture is revealed. Regional, national, and local contexts lead to different prioritizations of societal goals and the development of multiple and often individual ways to SPP. The focus on dimensions and aspects of sustainability within public procurement varies strongly from case to case. Furthermore, there is evidence of regional divides when it comes to the prioritization of sustainability dimensions in SPP, with divergent tendencies to concentrate attention on regulation and practices on the environmental or social dimension of sustainability within public procurement. We will explore this divide by considering national cases in SSA in the next section, followed by an exploration of the EU and some national cases within this regional economic community.

Examples from the Global South: The Social Focus of Public Procurement in Sub-Saharan Africa
In SSA, public procurement has long been seen as a key instrument of development, and that perspective has carried a very particular social dimension alongside the fairly obvious economic one. Thus, an analysis of the objectives of a range of public procurement law systems in SSA indicates the widespread use of public procurement for social policy purposes. These policies typically pursue a mix of economic and purely social objectives [9] (p. 381). The development of this approach to public procurement is closely connected to the historical and social contexts within which modern procurement systems evolved in SSA. Addressing widespread social development needs, alleviating poverty, and overcoming the colonial legacies of inequality dominated these developments.
Thus, in SSA, modern procurement laws typically included explicit social development objectives. South Africa is a prime example, as noted above. The introduction of broad modern public finance management governance, by means of the Public Finance Management Act 1 of 1999 (PFMA) [30], which included procurement governance, went hand-in-hand with the introduction of a comprehensive preferential procurement policy scheme under the Preferential Procurement Policy Framework Act 5 of 2000 (PPPFA) [31]. This scheme was explicitly aimed at giving effect to the constitutional mandate contained in section 217(2) of the Constitution of the Republic of South Africa, 1996, to implement "a procurement policy providing for [...] the protection or advancement of persons, or categories of persons, disadvantaged by unfair discrimination" [32]. This legislative scheme emerged from a policy development process that had its origins in a Green Paper on Public Sector Procurement Reform in South Africa, initiated jointly by the Ministry of Finance and the Ministry of Public Works in 1997. It is of particular interest to note the objectives highlighted by the two ministers (who were also two of the most senior members of the governing party at the time) in introducing the policy initiative. The Minister of Finance placed particular emphasis on the link between public procurement and the government's strategy "for employment creation and income generation" through "the promotion of small, medium and micro enterprises", stating that the "Government therefore embarked on a reform process to make the tendering system more easily accessible to small, medium and micro enterprises". In the Green Paper itself, this objective of supporting small, medium, and micro enterprises (SMMEs) is further explicitly geared "to eliminate the injustices of the past" [33]. The Minister of Public Works adopted a more explicit social focus in his introductory comments. He stated that the "appropriate orientation of public sector procurement would enable the State to use its purchasing power to attain specified socio-economic objectives". He located these objectives explicitly within the South African context, declaring that "public sector procurement can make a critical contribution to the transformation and democratisation of South African society" [33].
The Green Paper itself is explicit about its ideological stance in relation to procurement reform, stating: "The Reconstruction and Development Programme's aims and ideals provide the ideological backdrop to proposals for transforming the process of public procurement" [33]. The Reconstruction and Development Programme (RDP) was the post-apartheid government's most comprehensive policy framework. In the broadest terms, it was aimed at "a commitment to effectively address the problems of poverty and the gross inequality evident in almost all aspects of South African society", which it stated could only be achieved "if the South African economy can be firmly placed on the path of high and sustainable growth" [33]. These policy themes of socio-economic development linked to economic growth accordingly permeate the procurement reform Green Paper. Of particular relevance to the present purposes is the alignment between economic considerations of value for money and quality in procurement on the one hand and the social objectives on the other. Thus, the Green Paper explicitly aligned economic and social considerations in public procurement. It conceptualized the concepts of "whole life cost and value-for-money" to include "the advancement of marginalised sectors of society and achieving certain socio-economic objectives" [33]. Along this path there was an early interaction between economic considerations and social considerations in public procurement reform in South Africa, which included a precursor to what has subsequently become known as life-cycle costing. It is of further interest to note that the Green Paper also mentioned environmental considerations. In putting forward the idea of a points system for the award of public contracts that would balance price considerations against social development considerations, the Green Paper states that "points could, also, be awarded […] for environmentallyfriendly practices" [33]. In its concrete proposals for reform, the paper includes significant proposals on incorporating environmental considerations into procurement practices. However, an analysis of the Green Paper indicates that environmental considerations did not enjoy the same level of recognition compared to economic and especially social considerations. While there are proposals regarding the environmental dimension in the Green Paper, these are largely of an operational nature, for example that contracting authorities should "favour procurement of less environmentally damaging products" and influence suppliers to "comply with all environmental legislation", and not at the same conceptual level as the economic and social dimensions. The high level of integration between these latter two dimensions and the almost complete absence of integration of the environmental dimension is evident in the Green Paper. This conclusion is born out in the eventual translation of the Green Paper's policy proposals into a regulatory scheme under the PFMA and PPPFA. The procurement policy, as implemented through this regulatory regime, only provided for the economic and social dimensions. The environmental proposals all but disappeared from the scene.
While South Africa perhaps represents the most explicit and comprehensive example of the dominance of the economic and social dimensions of SPP over the environmental dimension, it is not unique in this regard in the region. For example, the regulatory regimes of Namibia, Botswana, Zimbabwe, Kenya, and Uganda all contain provisions giving recognition to the economic and social dimensions, while the environmental dimension is largely absent. The priority of the social dimension of sustainability and the weakness of the environmental dimension emerge strongly from all these systems. In these systems, one finds a similar interaction-although to varying degreesbetween the economic and social dimensions in the conceptualization of the procurement policy. For example, the Botswana Public Procurement and Disposal Act contains a part focusing on "Reserved and Preferential Treatment", which is introduced in Section 66(1) with the statement: "Pursuant to its economic and social objectives, the Government may from time to time introduce reserved and preferential procurement and asset disposal schemes" [34].
In addition, at the international level, economic and partially social aspects of public procurement are getting increasing attention, especially regarding developing countries. The International Labour Organisation (ILO) has tried to make the promotion of local resources one of its strengths, in line with a local resource-based (LRB) approach. More specifically, according to the ILO Employment-Intensive Investment Programme (EIIP), infrastructure development (i.e., the civil works sector related to roads, irrigation, water supply, soil conservation, etc.) has the potential to create jobs through employment-oriented investment policies and strategies by using local labor and resources that "create much needed employment and income, reduce costs, save foreign currency, and support local industry while increasing the capacity of local institutions" [35]. This typically involves small-scale contracting of local micro or small-and medium-sized contractors, or, when feasible (i.e., depending on the types of work, procurement options, and local circumstances), the local community-as a whole, as a specific group (youth, women, vulnerable families, indigenous groups), or as a small community enterprise [36].
Accordingly, under the ILO's EIIP, public procurement may be "targeted" in the sense that socio-economic targets are specified in tender documentation [37], participation by target groups is ensured to provide works, or optional contractual clauses are used to ensure specific societal requirements. For instance, the contractor may be asked to provide onsite "an adequate supply of drinking and other water for the use of his staff", or to have "due regard to recognise festivals, days of rest, and religious and other customs" [37]. On this basis, some "development objective" points are awarded to tenderers that ensure the use of local labor and/or of targeted groups of workers and/or of local resources at the contract performance stage. Therefore, the contractor is encouraged to actively involve and (also) train local entrepreneurs and communities at different phases of the investment project cycle (e.g., planning, implementing, and maintaining infrastructure) with a longterm positive impact on the society as a whole. This can be done by the main contractor directly or through the subcontracting mechanism.
Among others, Mauritania EIIP's example shows the positive externalities of using public procurement as a means of achieving further societal goals. Under the "Programme de Promotion de la Pierre Taillée (2005-2012)", cobblestone work has been developed to reduce high unemployment. To do so, local resources have been promoted, with stones in particular being used as building materials. Moreover, young unskilled people have been trained to become extractors, tailors, pavers, decorators, and masons. As a result, they have started their own small businesses and "a large number of roads have been paved with cobblestones" [36] (p. 26). In 2016, the social goal of reducing unemployment has been combined with the green objective of using clay as an eco-material for construction [36]. Here, the three dimensions of SPP seem to have been united in a single project.
Another example of the distribution of public funds at the local level through procurement is being developed in Kenya. In the upcoming regulation under the Public Procurement and Asset Disposal Act, "community participation" is included as a procurement method [38] (Section 131). This is a preferential provision for communities to be awarded public contracts if awarding the tender arguably contributes to "socio-economic objectives such as [the] creation of employment" (Section 131) and ensures that "the project has positive social outcomes with the community as its main beneficiary" (Section 132), especially concerning infrastructure tenders (see also [39]).
The focus of the social dimension of these policies is largely to channel economic opportunities to marginalized sectors of society in support of developmental objectives, primarily relating to poverty reduction, wealth redistribution, and equality more generally. Unlike social policy linkages in public procurement elsewhere in the world, those related to labor rights are not a major focus per se in SSA systems. Where the relevant procurement mechanisms-those implementing social policy considerations-do contain labor-related aspects, these have also focused on the paradigm of promoting marginalized groups as opposed to enhancing labor conditions per se. For example, the South African system of measuring broad-based black economic empowerment, which is the central mechanism for promoting equality objectives though public procurement, includes a skills development measure. This determines the supplier's contribution to developing the competencies of black employees as well as measuring the supplier's contribution to employing youth. In many cases, a range of mechanisms is used to implement these policy considerations in SSA procurement systems. Reservation schemes, in terms of which certain contracts are set aside for particular categories of bidders, and preference schemes, in terms of which comparative advantages are given to bidders from particular categories, are common. The criteria used to determine these categories and the measurement of the preference, again, typically reflect a mixture of economic and social policy considerations.
The environmental dimension of SPP has not been a major feature of procurement systems in Africa [40] (p. 3) and has only recently started to emerge slowly in a limited number of SSA countries. There are fledging initiatives in public procurement with an environmental focus in South Africa [29], Tanzania [41], and Uganda [42], for example. Many of these developments pertaining to environmental considerations, often using the terminology of sustainability, have been the result of the influence of various international organizations in African countries [43]. For example, The International Institute for Sustainable Development, the UNEP, and the World Bank, have been quite influential in promoting the sustainability perspective on public procurement, largely adding the environmental dimension to existing social and environmental policies in public procurement [43][44][45][46].
The new Namibian Public Procurement Act 15 of 2015 that came into operation in 2017 is one of the rare examples of the integration of environmental considerations alongside social and economic considerations in procurement policy. The act includes, as one of its objects, "to promote, facilitate and strengthen measures to implement the empowerment and industrialisation policies of the Government", which includes "preferential treatment in the allocation of procurement contracts to […] Namibian registered entities that promote the protection of the environment, maintain ecosystems and [promote the] sustainable use of natural resources" [47]. However, neither in the regulations nor in the guidelines issued to facilitate the implementation of the act is there any further details on how these environmental considerations are to be operationalized. Instead, one only finds a focus on social factors, such as the promotion of marginalized groups, in these implementation documents. A very similar scenario emerges from Kenya, where the 2015 Public Procurement and Asset Disposal Act states as a guiding principle in Section 3 the "promotion of local industry, sustainable development and protection of the environment" [48]. However, the underlying implementation mechanisms focus largely on social and economic considerations, and the implementation of these is generally weak [39,49,50]. In Kenya, the implementation of environmental aspects into public tenders is mainly limited to pilot projects by parastatal bodies [39]. The Ghanaian parliament enacted a procurement law that includes the environmental dimension and provisions in procurement regulation that entail concretizations. The Ghanaian Public Procurement Act calls for the procurement of the most energy-efficient products (air conditioning systems). These developments can be interpreted as an increasing attention toward the environmental dimension of sustainability in public procurement in SSA. If and how fast this becomes a new, widely implemented norm remains to be seen.

Examples from the Global North: The Environmental Focus of Public Procurement in the European Union
In the case of the EU, the development of SPP followed a unique path. While public procurement is normally subject to the sovereign decision making of countries, in the EU context, it is subjected to the prerogative of the enabling, and development, of a common internal market. Pursuant to the internal market promotion, economic policies have been harmonized as much as possible. On the contrary, social policies have usually been left to each member state. Mirrored in the public procurement context, this has implied that non-discrimination, equal access to internal markets of member states, and economic efficiency (or, using the World Bank's wording, "value for money") have been emphasized much more than any other objective. To achieve economic efficiency, public procurement has been opened up to competition by giving tenderers from different member states equal opportunities to bid for public contracts. Therefore, the principles of equal treatment, transparency, and non-discrimination created the basis for procurement regulations in the EU and its member states. Therefore, regulations on public procurement were rather restrictive toward all nonprice-based aspects, including environmental and social aspects. McCrudden identified this as a "Chilling Effect" [51] (p. 331) of European procurement regulation on social procurement linkages during the 1990s. The EU's regulations on public procurement, which have to be transposed into national laws by the member states, have focused on enabling fair competition in the common market in order to guarantee transparency, equal treatment, and non-discrimination. Generally, this has resulted in a preference for limiting the discretion of procurement officials as much as possible and a focus-and over-reliance-on the lowest price criteria for awarding tenders (placing emphasis on the economic dimension). This has dramatically changed more recently in favor of SPP. Member states' practices, the Court of Justice of the European Union (CJEU) case law, and the new award criteria in the directives have opened up to other qualitative criteria, dubbed "secondary objectives" in the past, namely environmental and social criteria [39].
The opening up of procurement regulation to non-price aspects, and linkages between public procurement and sustainability considerations, were also triggered by municipal actors who tested the boundaries of the procurement directives regarding the integration of environmental aspects.
Municipal frontrunners massively helped to change this and subsequently influenced reforms of EU regulations themselves based on court decisions (see [52]) (p. 203). A short analysis of the regulatory changes can give us some information about the approach toward the different dimensions of SPP within the EU.
From the outset, the attention of the EU has been focused more on the environmental aspect of public procurement, or Green Public Procurement (GPP), as it is usually referred to. This continues up to today, given the proliferation of guidance and tools issued by the EU commission on GPP and the dearth of instruments available to guide procurement entities on how to best implement social goals. For example, in a number of cases, the EU enacts legislations that foresee obligations on contracting authorities to purchase 'green'. Examples are Regulation (EC) No 106/2008 (the so-called EU Energy Star Regulation) [53], through which the EU obliges contracting authorities to purchase products according to energy-efficiency requirements, or with Directive 2009/33/EC [54], which is the Green Vehicles Directive on the promotion of clean and energy-efficient vehicles. In many cases, the EU calls on contracting authorities to "play an exemplary role in the field of energy efficiency" [23]. Caranta and Cravero also cite Directive 2012/27/EU on energy efficiency [55], Directive 2009/28/EC on the promotion of the use of energy from renewable sources [56], and Directive 2010/31/EU on the energy performance of buildings as examples [57]. Such a leading role from the EU legislator in such a specific way has enabled the development of a strong EU policy and approach on GPP [23].
Social aspects, with a domestic focus or with an international one, including human rights and labor regulations in international value chains, have been integrated into regulation more recently and only on an optional basis. Social considerations have also been mentioned. According to the Interpretative Communication of the EU Commission on the "Community law applicable to public procurement and the possibilities for integrating social considerations into public procurement" [58], the expression "social considerations" covers a very wide range of issues and fields: from ensuring compliance with fundamental rights and with principles of equality of treatment and nondiscrimination to the inclusion of preferential clauses, such as those "for the reintegration of disadvantaged persons or of unemployed persons, and positive actions or positive discrimination, in particular with a view to combating unemployment and social exclusion" [59]. Nevertheless, this preferential approach may be adopted in very different ways from one national context to another. However, it may not encompass reservations for marginalized groups, in contrast to the approaches to social considerations in the procurement regulation of countries in SSA.
It is only with the 2004 directive, after the endorsement of SPP criteria by the CJEU case law [60] (p. 38), that the EU procurement legal framework started to explicitly allow the possibility of including GPP criteria in the procurement process. However, there were limitations, most notably the link to the subject matter of the contract and more general requirements that these criteria are applied in a neutral and non-discriminatory manner [61]. Even though experts made the case for social aspects being permissible already under the 2004 directive [62]  Public procurement should now help to "achieve smart, sustainable and inclusive growth" [64] (Preamble, Paragraph 2). Since the 2014 directives, it has become unambiguous that not only environmental, but also social objectives can be part of public tenders. However, the focus of more specific regulations lies again with environmental aspects such as lifecycle costing and ecolabels. Social aspects have often been associated with compliance with external legal norms and requirements (e.g., compliance with ILO conventions or with social security regulations). As Arrowsmith argues, this has been done for a variety of reasons, including avoiding associating the government with unlawful behaviors, providing an additional enforcement tool, and avoiding firms that do not comply with such requirements and thus enjoy an unfair advantage [66] (pp. 696f). The implementation of such requirements does not usually create any problems of transparency or compliance with the EU directives. Arrowsmith argues that "where procurement policies focus on compliance with existing general norms there is generally no problem over transparency in the standards that firms must meet, as these are set out in the relevant legal norm (such as criminal legislation). The fact that the procuring entity does not set the standards also reduces the scope for the procuring entity to abuse discretion by setting standards that favour particular firms" [66] (p. 698). Polies that go beyond compliance with general rules are also common. In fact, as Arrowsmith argues, procurement is often used to overcome the obstacles that characterize the legislative process [67].
The supportive measures for the implementation of SPP, such as guidelines, exemplify the division between social and environmental aspects in the EU. Social aspects are already mentioned in the European Commission's (EC) Buying Green! handbook from 2004, but it took six more years until the commission published similar guidelines for Socially Responsible Public Procurement (SRPP), which continues the division between GPP and SRPP. The handbooks on GPP by the EC illustrate the broadening of the understanding of sustainability in public procurement quite well. While in the first edition from 2004, the only reference to the social dimensions was the mentioning of the concept of sustainable development, which, beside environmental, also covers economic and social aspects [68]. The second version, from 2011, referred to its parallel publication on socially responsible public procurement: the Buying Social handbook [69]. The social dimension was now encompassed into the idea of SPP within the EU, but it is dealt with separately from the environmental one. In addition, in the third edition-the Buying Green! handbook of 2016-social considerations are not covered [70], and there has been no further version of the Buying Social handbook, even though a new version is currently planned by the Directorate-General Internal Market, Industry, Entrepreneurship and SMEs (DG GROW). In addition to the directives that deal specifically with environmental issues, the EC has developed tender criteria for 20 product groups to further integrate environmental aspects into public procurement [71], while there is no such guide for social criteria. This is not to say, of course, that social aspects have been completely neglected by European countries. There were European experiences of social considerations in public procurement before the uptake of the sustainability discourse, which therefore precede the newer environmental considerations. The societal goals of upholding labor standards and generating employment, hindering discrimination, and guaranteeing status equality have been part of public policies, including public procurement in some European countries, since even before the Second World War [51] (p. 77). Furthermore, Semple underlines that "service and works contracts awarded by local or regional governments in particular have long been seen as means of implementing various social policies" [72] (p. 294). In contrast to the long-standing and ongoing process to use the lever of public procurement as a pillar in public policies for marginalized groups, in many countries in the Global North and South e.g., in South Africa, Kenya, India, and the United States of America, the economic integration within the EU and the central role of the competition law limit the scope of social criteria directed at the societal goals of EU member states. Therefore, EU member states have limited options to integrate domestic social considerations into their public procurement regulation. In addition, social considerations that apply to international value chains have been receiving attention only recently, and with limited implementation.
The kind of SPP with an international focus along global supply chains has been-and to some extent still is-constrained by EU regulation. Indeed, while on the one hand the 2014 EU Directive on Public Procurement explicitly allows the possibility of pursuing social and environmental goals (endorsing the social and environmental dimensions of procurement), on the other hand, it limits the possibility of pursuing such goals through the conditions that such goals are linked to the "subjectmatter of the contract" [64] (Art. 70) and "are proportionate to its requirements and as long as the principles of value for money and equal access for all EU suppliers are observed" [73] (p. 5). This limitation has meant that the possibility of pursuing broader sustainability goals linked to the overall operation of companies is, if not completely precluded, certainly badly constrained. The directives allow the process and method of production to be taken into account, but only in relation to the goods related to the subject matter of the contracts. Therefore, it is not surprising that SPP, with a broad international focus, still plays a marginal role in overall procurement in the EU. This is despite strong international commitment to that effect. For example, the 2011 United Nations Guiding Principles on Business and Human Rights (UNGP) and, more recently, Comment 16 of the Committee on Economic Social and Cultural Rights, have made clear that the state has an active obligation to ensure that companies that do business with the government respect human rights.
The initial national action plans for SPP of most of the EU member states indicate a strong bias toward GPP [27] (pp. 457f). This has not changed significantly up to today, although, for some time now, there have been calls for the public sector to "move beyond an initial focus on environmental issues to address a more holistic range of sustainability aspects through its procurement" [74] (p. 220). Based on the concept of sustainable development, an aspiration for an equilibrium between the different dimensions is expressed in the regulations on public procurement, even though this did not translate into procurement practice. In 2017, a study on 10 EU member states that was prepared for the European Commission still found that "GPP presents the most mature and institutionalised approaches to strategic public procurement compared to SRPP and PPI" [75] (p. 4). This is also mirrored in the transposition of the EU procurement directives into national regulation.
This focus on environmental aspects is also visible in German municipalities, which control around half of the overall public procurement budget. Environmental objectives in public procurement have quickly become more integrated into municipal regulations and in tenders [76]. This mirrors the corresponding experiences with SPP in the private sector. Research on private sector supply-chain management took a similar development that started with the integration of environmental aspects and only recently started covering integrated approaches (see [27]) (pp. 454f). Today, environmental considerations are fairly widespread, while social considerations with an international scope, as described above, are still being tested by frontrunners. In general, we can observe a strong emphasis on environmental considerations when it comes to public procurement in the EU member states, up to today. Based on the EU procurement reform, Germany amended its Act Against Restraints in Competition (ARC) in 2017, thereby including the option to consider innovative, social, and environmental aspects in public procurement [77] (Section 97, 3). Social aspects in international value chains are not explicitly mentioned. This leaves the decision to actually implement those criteria with the respective subnational levels of governance and, if they do not make those mandatory in their regulations, to the procuring entity itself, such as municipalities. Other member states, such as the Netherlands and Austria, also transposed the EU directives without mandatory regulations on sustainability issues. However, they have ruled out the use of price as the only award criterion in public tenders [78] (p. 84), which gives qualitative aspects, such as sustainability criteria, more weight in tender processes. While sustainability aspects in public procurement are in general still met with some scepticism in Germany, as described by Stoffel, Müngersdorff, and Vrolijk [79], there have been developments toward integrating social considerations. In recent years, domestic social criteria have become part of procurement regulations in some German states, including social criteria along international value chains. Of the 16 German states, 11 refer to the ILO core conventions in their procurement laws. Most of them limit their scope to specific 'sensitive' product groups (that have a high risk of violations of the core conventions, such as textiles or IT hardware) and define them as a general or optional criteria within the procurement process [80] (pp. [53][54][55][56][57]. At first three, now only two, states integrated the ILO core conventions in their procurement regulation, which were to be used as mandatory criteria in public tenders for sensitive products. While these are interesting developments that are indicators of a rising interest in the social dimension of public procurement, the integration of social aspects regarding domestic and international value chains in procurement procedures and finally in tenders is not widespread. Effective implementation is largely limited to specific pilot projects, even in the case of mandatory provisions [80] (p. 56). In this way, processes and criteria are being tested, especially by municipal actors. Just recently, a project was started by the Make ICT Fair Campaign, to test approaches to the socially responsible procurement of Information and Communication Technology (ICT) hardware, together with European piloting municipalities, among them Barcelona, Stockholm, and London [81]. Serious attempts to make social criteria along international value chains the norm in public procurement are still sparse. Public bodies that create staff positions to advise policy makers and especially procurement officials, such as the city state Bremen, have made the most progress so far.
Some municipalities have integrated specific aspects, such as the exclusion of child labor from products procured, into municipal procurement regulations, even before the transposition of EU regulations into German law. In 2011, 170 German municipalities had adopted council decisions against exploitative child labor in their procurement; a campaign to increase this number was started by nongovernmental organizations in 2010 [82]. German municipalities are also making use of the option to rely on ethical trade, as part of the EU directive, e.g., by opting for Fair Trade products, even though it is not mentioned in the ARC or most of the state laws and regulation. A total of 612 German municipalities are Fair Trade Towns [83] that commit themselves to procure some products, such as coffee, under the Fair Trade Standard. However, in view of the fact that there are more than 10,000 municipalities, this is only a weak indicator for a trend toward the integration of international social considerations. At the federal level, concrete actions such as the guidelines on the sustainable procurement of textiles are still being developed. When this process is completed, it will mean a partial integration of social aspects into federal procurement processes. The original goal was to procure 50% of textiles under consideration of social and environmental aspects by 2020 [84].
While Germany, at the federal level, is reluctant to push for social considerations along international value chains in regulation and praxis, and few municipalities use the regulatory leeway for implementing SRPP, the Netherlands implemented the concept of "Social Conditions", which includes international labor standards. From 2013 on, all contracts of the national government (that exceed the EU thresholds for Europe-wide tenders) had to include these social conditions [85] (p. 1). However, as the Dutch government established its goals for sustainable public procurement in 2005, the focus was solely on environmental aspects [85]. In the 2011 criteria documents, environmental sustainability requirements were described for 45 product groups; since 2012, social requirements, including labor standards and human rights along international value chains, have been added [85] (p. 3). Although these measures are more advanced, when compared to the situation in Germany, implementation is sparse, as the social conditions recommended by the Dutch government are not integrated into most tenders [85] (pp. 6f). Again, at the municipal level there is some progress on the integration of international social considerations into public procurement practices. The city of Rotterdam integrated them into its recent Action Plan for Social Responsible Procurement of December 2017 [86].
Regarding domestic social objectives, local public bodies already adopted those in the 1980s, in contrast to central government procurement practices in the Netherlands [51] (p. 609). Even in 2014, the national action plan on human rights by the Ministry for Foreign Affairs states that it has to be verified if the integration of international social aspects into public procurement is in accordance with OECD guidelines [87].
Other European countries, such as Sweden and the United Kingdom, have had a greater focus on domestic social issues in their procurement regulation. In Sweden, the linkages between social objectives and public procurement started with domestic policy issues, such as racial discrimination. The City of Malmö was the first to adopt an anti-discrimination clause in their procurement [51] (p. 417). The White Labour initiative in Malmö, against unemployment and social dumping, was directed at domestic societal considerations, but is seen as the starting point of SRPP in Malmö, including international social considerations [79]. Municipalities in Sweden explicitly try to catch up with GPP in recent years, such as Malmö, where a staff position to strengthen GPP was created in 2015 [79]. In the UK, race equality had already been integrated as an objective into public procurement in 1988 [88], but although provisions on racial equality have a long history, they do not directly address or use public procurement to remedy the situation of unequal treatment of different races and genders. They merely impose a "broad duty of equality" on public authorities [51] (p. 88). The potential legal leeway for that was not used by local public bodies, and McCrudden found a lack of administrative back up and an absence of guidance to be part of the reason for it [51] (p. 606). The recent Social Value Act is another example from the UK of domestic social and economic objectives in public procurement. While its implementation is also not widespread [89] (p. 21), municipal frontrunners such as the city of Preston are exploring the options of this legislation [79]. While the situation regarding strong domestic social considerations and a rather late adaption of environmental considerations distinguishes the UK and Sweden from Germany and the Netherlands, they share the recent integration of international social considerations into their public procurement regulation. In England and Wales, exclusion grounds for tenderers specifically include violations of "environmental, social or labour law obligations anywhere in the world" [90] (p. 248). In Sweden, the Code of Conduct for Suppliers of 2013 already includes social aspects related to international value chains, such as human rights and ILO core labor standards [91].
The introduction and implementation of SRPP and GPP in Europe have been handled differently in the member states. In general, domestic social objectives have been taken into account for longer periods now, although not to the extent of countries in SSA such as South Africa and Kenya. With the emergence of SPP in the wake of the discussion about sustainability transition, GPP was the first to be integrated into public procurement practices in most cases, slowly and only recently followed by first attempts and pilot projects for international social criteria, such as the ILO core conventions and human rights issues along international value chains.

Conclusions: The Future of Multidimensional Sustainability in SPP
The analysis of different approaches to and implementation of SPP in SSA and EU, as depicted in Table 1, proves not only that the prevalent generalization of a predominance of environmental considerations in SPP worldwide is false, but also that national and sometimes even local discourses define the scope and dimensionality of SPP. Biases within the social dimension of sustainability are often based on specific national aspects that can be subsumed within the sustainability discourse but do not necessarily originate from it, such as the redress of past injustices in many countries in SSA or the social consideration of child labor along international value chains by many German municipalities. Many of those social considerations with a domestic and local scope in SSA and the EU alike, predate the sustainability discourse. Based on our two-dimensional classification of SPP, with the economic, environmental, and social dimensions of sustainability on the x-axis, and the spatial scope of the effects of SPP-whether local, regional, or international-on the y-axis, we were able to further differentiate between the foci and developments of the multidimensionality of SPP in the EU and SSA. Our hypothesis of a converse bias in the focus on GPP and SRPP could be partially verified for the EU, some of its member states, and many countries in SSA.
By conceptualizing the discourse on the different dimensions of sustainability, we have aimed at bringing to the fore the importance of paying equal regard to all dimensions of sustainability. By showing and comparing concrete examples the implementation of the three dimensions of sustainability, we could show the context sensitivity of multidimensionality in SPP that sparsely allows for generalizations. One generalization that can be made is the dichotomy of the dimensional biases in SPP in SSA and the EU.
Horizontally, social aspects have been part of procurement regulation in European countries, but they play a less central role and are not as encompassing as they are in countries in SSA. Social aspects of procurement have mainly remained focused on labor rights (including the disability and social security aspects of labor rights) within the respective national context, to be implemented within the (limits of) existing legislation and prescriptive regulation (including collective agreements and contracts) and within the limits of the 'mutual recognition' principle. They are focused on labor rights and, apart from the preferential treatment of sheltered workshops, not on issues of social justice. When we look into the transposition of the EU regulations into national laws and then further at the implementation of the options those regulations provide, we see a strong bias toward the environmental aspects in public procurement.
Vertically, the EU and its member states have partially begun to extend the scope of social aspects in public procurement toward international labor rights. Not only can social aspects be included in procurement decisions that have domestic effects (within the respective member state or the EU as a whole), but also those aspects that concern international value chains, e.g., through provisions for ethical trade or for ILO core labor standards. Many European actors just recently undertook efforts to integrate adherence to ILO core conventions into subnational regulation and into specific tenders, thereby taking on responsibility for sustainable production and consumption in the producing countries of the Global South. Social objectives geared to international value chains are possible under EU regulation, but they are sparsely and differently implemented in its member states. More importantly, making effective use of political leeway to integrate international social aspects, such as the ILO core conventions, into public tenders is not a new norm, but rather is based on some pilot projects by frontrunner institutions, which are often municipalities.
We could not find evidence of a coherent integration of the three dimensions of sustainability in the regulation and practices of SPP in SSA or the EU. What we could observe was a tendency to further integration of the dimension that is less pronounced.
In SSA, environmental aspects have found their way into the policy documents and regulations of many countries, but the emphasis clearly lies with the social and economic aspects of public procurement. The implementation of environmental criteria is rare, and the efforts of governments, e.g., in South Africa and Kenya, are concentrated on the effective implementation of social criteria in public tenders with a domestic scope, aimed at fostering economic development, the preferential treatment of specific societal groups, and redressing the discriminations of the past. However, pilot projects and a growing interest in environmental aspects in public procurement might set the course for a new trend.
There are many social conditions in EU regulation of public procurement; however, the emphasis remains on enabling equal access to the common market. Reservations or preferential treatment beyond the narrow focus set by the EU directives, as in SSA, are not possible. The recent reform of EU regulation, as well as new laws in many countries in SSA, such as in Ghana and Kenya, show an increasing tendency to integrate the previously neglected environmental dimension within strategic objectives in public procurement, and therefore present the full horizontal spectrum of sustainability dimensions. On the one hand, there is an increasing integration of the respective missing sustainability dimensions; on the other hand, there is an ongoing separation of the dimensions in regulation, supportive measures, and practices on all levels of government. Additionally, international social considerations in public procurement in European and environmental considerations in SSA settings are still sparsely implemented.
One has to consider the role of path dependencies in different country contexts, which relativizes a strict north-south divide in the orientation toward the environmental or social dimension. We identified a bias in the cases in SSA and the EU, that allows for a regional differentiation, that negates the world-wide generalization of UNEP cited above, as regards a bias on environmental considerations in public procurement. While many countries in the Global South share a concentration on social aspects in their approaches to SPP, such as South Africa and India, others, such as Brazil and Mexico, are also focusing strongly on environmental criteria [63] (pp. [21][22][23][24]26). In both regional contexts, EU and SSA, sustainability is not used as a unifying concept to integrate the different dimensions, especially the environmental and the social ones, into public procurement. However, does this mean that the concept of sustainability is useless in integrating such objectives effectively into public procurement?
A multidimensional concept of sustainability might still act as a door opener for integrated solutions. Abstract concepts of sustainability did not start sustainable procurement practices; the respective societal discourses seem to be far more important. The 'white labor' initiative in Malmö, the will in German municipalities to prevent child labor, and the redress of past injustices in SSA were the starting points for concrete administrative actions and regulatory changes in all these settings. Despite the clear separation between GPP and SRPP within national and international approaches toward SPP, the country examples analyzed in this article show an increasing integration of the respective neglected dimensions in Europe and Sub-Saharan Africa alike. European countries are exploring options to integrate social aspects along international value chains into their public procurement, with municipalities acting as frontrunners that engage in an increasing number of pilot projects, such as in the Make ICT Fair Campaign. In SSA, countries initiate regulatory changes and occasional pilot projects, such as the pilot tenders by parastatals in Kenya to integrate environmental concerns. The current situation is defined by a trend to integrate more dimensions of sustainability (horizontally), such as GPP in SSA and SRPP in Europe, including social return, and to extend the scope from the domestic to the international in the EU (vertically).
SPP can be used as a general guide to overcome path dependencies and find a middle way for an increasing integration of both environmental and social aspects into the practices of public procurement. Experts, policy makers, and practitioners can look for ways in which they can overcome the path dependencies in their respective regulatory frameworks, using sustainability as a guiding principle. Concepts and strategies for sustainability focus on the connection between the three different dimensions of sustainability. Researchers point out the missing focus on the integration and coherence of policies regarding a unified approach toward sustainability. However, the problem goes further than to integrate all dimensions of sustainability in policies and programs, as well as monitoring and assessment. In the examples gathered in this article, it becomes visible that the environmental, the social, and the economic dimensions do not automatically interlink.
Sustainability might be a category too broad to operationalize in terms of administrative action, but it is an important aspiration to reach all interconnected dimensions. Environmental and social challenges in the production and value creation process have to be equally addressed. Apart from general challenges to the integration of multiple issues in a three-dimensional concept of sustainability, the integration of different aspects in public procurement does not automatically evolve from a coherent concept of sustainability. The lines that separate different approaches to sustainability, or only the attention to certain aspects within administrative action, such as procurement, are themselves defined by the different administrative units and also depend on product groups and sometimes even specific products. Attention to and the implementation of SPP may be separated by administrative competencies, as different public sectors have their own platforms and exchanges on procurement and sustainability. There, overarching national and subnational strategies and supportive measures for SPP might help to bridge this administrative gap. Top-down, but also horizontal, communication is needed to connect different approaches and dimensions. Furthermore, strategic procurement and the professionalization of procurement might help integrate different competencies and enable SPP in all its dimensions.
Different approaches and possibilities for sustainable supply chains are often defined by circumstances and processes within product groups or sectors. The variation in complexity and manifestation of supply chains, as well as the progress already made toward social consumption and production in specific products, defines the current potential for SPP. A multidimensional concept of SPP does not automatically lead to a multidimensional understanding by bidders in regard to their supply chains. Here, the communication with the market has to reflect a unified concept of sustainability. At this moment in time, this might not be entirely possible, as many public authorities do not have a concise unified approach to multidimensional sustainability themselves. The complexity of the concept of multidimensional sustainability might overstrain the competencies and capacities of many public authorities that have to organize their own procurement. As long as implementation, including the control of sustainability aspects along domestic and international value chains, is placed nearly entirely under their responsibility, procurement processes will only present a patchwork of sustainability aspects. In any case, the single procurement authority cannot succeed with effective implementation if left alone or left with insufficient means to handle the complexity of SPP. Municipalities in particular are often caught in a struggle between their frontrunner status, due to their engagement with different dimensions and aspects of sustainability, and their limited resources.
Right now, implementing SPP means adding further considerations to the procurement process. Public entities in countries already concerned with environmental considerations have to integrate those as well as work on and experiment with additional social considerations, and vice versa. Procuring entities need the support and resources to deal with these additional tasks. While Bartens and Winter show that SPP is chosen as a course of political action, to translate the merely theoretical concept of sustainability into concrete action [91], the political will to strengthen and promote sustainable production and consumption through sustainable public procurement is often limited to a specific, cultural, national, and local understanding and interpretation of sustainability and specific topics within and apart from the sustainability discourse, such as environmental concerns, and concerns about child labor or about modern slavery. This also conveys different perspectives on justice in the sustainability discourse. In the EU, there are indications of a stronger concentration on intergenerational justice, focusing on environmental issues in order to preserve the environment for future generations. In SSA, intragenerational justice seems to be more pressing. However, all actors must be aware that analyzing challenges through the lens of concepts of sustainability is a chance to include both aspects. Without environmental considerations, future development is not possible or will have non-desirable effects. Without a broader scope for social considerations in the EU, the developed countries fall short of their own responsibility to, at least, do no harm with their economic activities.
Funding: This specific research received no additional external funding.