More or Less Sustainable? Assessment from a Policy Perspective

: Sustainability of tourism destinations has become the main focus in planning and managing tourism development. Despite existing legislation and an institutional framework to safeguard balanced tourism growth, many destinations fail to properly address it. So far, studies are limited in exploring sustainable tourism impacts from a policy perspective. This study follows previous ones in using the triple bottom line sustainability approach to define tourism impacts. It argues, in particular, for a nexus between understanding of policy perception and sustainability, and it applies this to tourist destinations in Serbia to determine whether they are operating sustainably. For this purpose, the data were collected using а combination of multiple methods, involving interviews with policymakers and content analysis of strategic documents. This study further suggests a model that assesses the extent of the sustainability of tourist destinations. The results illustrate the importance of understanding policy perceptions in shaping and facilitating sustainability and informing policy enablers on how to improve and reform current tourism development. The model can be adopted and applied to any tourist destination facing an inevitable need to re-shape their tourism development plans and policies, while the implications address the need to build a participative policy approach to sustainable tourism development.


Introduction
The concept of sustainable development emerged from environmental concerns within the activities of the United Nations, reflected in the World Charter for Nature [1] and Agenda 21 [2]. It was further reoriented towards tackling socio-economic issues and reflected in a "triple pillar" context within the World Summit on Sustainable Development in Johannesburg in 2002 [3] and Rio +20 "The Future We Want" [4]. Consistent with [5][6][7], this concept is understood as an organizing principle for meeting human development goals while sustaining the potential of natural systems to supply the natural resources upon which society and the economy depend while aiming at achieving social, environmental, and economic progress [8,9]. Thus, sustainable development as a concept incorporates social, ecological, and economic aspects, outlining the necessity of their optimization to meet 17 sustainable development goals with 169 targets of the United Nations' Agenda 2030 [10]. However, achieving all this has been often hampered by some trade-offs and different interpretations in favor of economic growth, at the expense of social well-being and ecological viability [11].
Tourism sustainability has been long debated, and many studies from various approaches open a variety of interpretations so far. Regardless of the level of inter-dependency (destination sustainability, tourism sustainability, and sustainability of the local community), understanding the principles of Sustainability 2020, 12, 3491 2 of 16 sustainability are fundamental for sustainable tourism development [12][13][14]. The concept generally rests on the three theoretical pillars, representing socio-cultural, environmental, and economic tourism impacts. As such, the concept has been integrated into tourism strategies starting from a local to a global level. Taking into consideration various impacts tourism has on destinations, understanding stakeholders' perception is essential in minimizing potential negative effects and maximizing benefits, so an understanding of sustainability from different perspectives by those who live in the destination or use and manage resources means meeting the needs and requirements of all stakeholders (local communities, tourists, operators, and regulators). It is tourism that unifies all, boosting destinations to a higher quality in the short and long term, but, in order for sustainable tourism to be achievable, all tourism segments must work towards becoming sustainable, even if it looks like an incalculable goal and unattainable objective [15,16]. Many scholars argue about different aspects of perceptions of the sustainability of tourism, yet studies are very limited in putting the focus on policy enablers' perception [17][18][19][20][21][22]. This study follows previous findings in using the established three mainstream pillars of sustainability (socio-cultural, environmental, and economic) to define tourism impacts. It adds to the literature gap by assessing the level of tourist destinations' sustainability from a policy perspective. The policymakers represent the regulators: those who contribute to managing and controlling tourism development at the destination level (such as governmental bodies, contributors to management strategies, tourist organizations, etc.). Additionally, this study suggests a modeling framework for strategic tourism development reforms. The proposed model posts directions for the systematic organization of policymakers to infer conclusions regarding the current state of well-being of tourist destinations. It is important to assess this due to the manner of progress and to direct and monitor policies towards sustainable development.
Serbia was chosen for a case study as it seeks to develop tourism despite limitations in many aspects (lack of finances, low GDP, small investments in tourism, etc.). So far, studies have been undertaken on tourism stakeholders in Serbia [22,23], but, to our knowledge, this approach is still missing from the literature. The paper sets out the theoretical context concerning sustainability. This is followed by a brief overview of related facts and figures about the study area. The next section presents the conceptual model and methodology, followed by empirical results. Findings are discussed, followed by the concluding part of the paper.

Literature Review
Sustainable tourism has evolved from the original sustainable development concept, being able to "process the need of the present without compromising the ability of future generations to meet their own needs" [24] (p. 8). Since then, vast debates about the definition have ensued, resulting in the incorporation of sustainable development in the context of tourism needs, resulting in the definition of sustainable tourism. In general, this concept has become very popular and ever since continued to raise dilemmas about its validity and operationalization.
Over the years, as it gained in popularity, researchers extensively debated sustainable tourism issues [25]. Various aspects of sustainability were discussed, each from a different angle of scientific approach [26], yet many aspects of sustainable tourism are still overlooked in the literature, in terms of achieving a systematic perspective and an interdisciplinary approach, like the role of tourism demand, the fixed entity of tourism resources, the imperative of intra-generational equity, keeping the culture intact and usefully measured sustainability, and there has been some skepticism about tourism forms of sustainable development [27]. Some exceptions have been noted by [28,29], when arguing the case for one-site measurement used as an impact control measure and thus explaining the role of tourism demand from a sustainability perspective. An exceptionally strong focus on preservation and conservation of resources is argued for by addressing different aspects of the sustainability of tourism resources, like macro and micro sustainability approaches [30], "strong" and "weak" sustainability [31], the minimum resource condition to maintain constant stock [32], etc. Issues of inter-generational equity Sustainability 2020, 12, 3491 3 of 16 in favor of intra-generational equity as an essential prerequisite of sustainable tourism are highlighted by [33,34].
Furthermore, many scholars have debated the issue of measuring sustainability by trying to identify sustainable levels of tourism development and how these can be measured. Different methodologies with a comprehensive set of indicators are proposed, and the debate is still ongoing [15,16,[35][36][37][38], yet there is no consensus on a universal list of indicators capable of revealing the sustainability level of various destinations.

Study Area: Serbia
Tourism in Serbia is recognized as one of the priority areas for development and an important task on its path towards European Union (EU) integration (Table 1). At the national level, tourism development is under the jurisdiction of the Ministry of Trade, Tourism, and Telecommunications, responsible for legal regulative measures, strategic planning and control. The main role in the marketing and promotion of tourist destinations at the national level is played by the National Tourist Organization. There are several regional tourist organizations, development agencies and tourist clusters having a direct role in tourism development and marketing. At the local level, such activities are under the control of municipal authorities and local tourist organizations. Overall, in the tourism planning and development process, a top-bottom approach is applied. This particularly concerns the issues related to infrastructure and capital investments. Table 2 presents a summarized framework of the institutional structure of tourism policymakers in Serbia. General sustainability frameworks are set within The National Strategy on Sustainable Development [64] and the Strategy of Tourism Development 2016-2025 [65], while different issues, measures, and goals are being emphasized in various strategic documents. They provide the overall line with the general sustainability concept, directed towards the proper balance between the three core pillars. Commonly, the focus is placed on those issues concerning the proper use of natural resources, while recognizing solid institutional capacities for sustainable tourism development [66][67][68]. Many additional plans and projects further address the process of development of tourist destinations of Serbia (like regional plans, tourist destination master plans, and municipal development plans). Still, policymaking in Serbia's tourist sector is in a transitional phase generally due to the bureaucratic and autocratic system. Political decisions regarding sustainable tourism were mostly modeled on EU policies, based on various EU strategic frameworks and effective instruments (the Territorial Agenda of the European Union in 2007 [69], the European Union Strategy for Sustainable Development in 2006 [70], and the Agenda for Sustainable and Competitive European Tourism in 2007 [71], etc.). In the National Strategy of Sustainable Development [64], the fundamental concept of sustainable development is overgeneralized. Here, tourism is identified as an emerging sector with significant environmental impact but short of precise objectives or priority actions to make it more sustainable [72]. There have been frequent changes in legislation in all domains. However, these documents typically represent bare plans and political statements with little possibility for realization, commonly overusing and misunderstanding the concept of "sustainability". Even if the development of general and sectoral plans/strategies and programs has been intensified, there was a notable lack of inter-sectoral coordination and cooperation [72]. Often, national policies and strategic documents were elaborated by third parties, frequently engaging foreign experts unaware of pivotal national concerns and the current situation at destination levels. Thus, questions are raised about the realistic possibilities and the justifications for their practical implementation. This highlights a need for the creation of cooperative stakeholder networks in the policymaking process. As the tourism sector involves a vast number of stakeholders, this should lead to a dialog and negotiations to develop commonly desirable policies [73,74].

Materials and Methods
As the focus of the study was to understand policy enablers' perception of the sustainable development of tourist destinations in Serbia, a multi-stage methodology was chosen. The study applied the scholarship research approach [75] and combined theoretical and practical knowledge. This involved collecting data from using a qualitative (expert's judgment and content analysis) and quantitative method (interviews). The study followed the three core elements of the sustainable tourism conceptual model [76], including a modest set of indicators extracted from the European Tourism Indicator System (ETIS) [77] (Figure 1). In this line, the research queries hypothesize impacts by surveying policy-enablers' opinions. Structural equation modeling (SEM) was applied, which represents the relationships and critical paths between the factors. been intensified, there was a notable lack of inter-sectoral coordination and cooperation [72]. Often, national policies and strategic documents were elaborated by third parties, frequently engaging foreign experts unaware of pivotal national concerns and the current situation at destination levels. Thus, questions are raised about the realistic possibilities and the justifications for their practical implementation. This highlights a need for the creation of cooperative stakeholder networks in the policymaking process. As the tourism sector involves a vast number of stakeholders, this should lead to a dialog and negotiations to develop commonly desirable policies [73,74].

Materials and Methods
As the focus of the study was to understand policy enablers' perception of the sustainable development of tourist destinations in Serbia, a multi-stage methodology was chosen. The study applied the scholarship research approach [75] and combined theoretical and practical knowledge. This involved collecting data from using a qualitative (expert's judgment and content analysis) and quantitative method (interviews). The study followed the three core elements of the sustainable tourism conceptual model [76], including a modest set of indicators extracted from the European Tourism Indicator System (ETIS) [77] (Figure 1). In this line, the research queries hypothesize impacts by surveying policy-enablers' opinions. Structural equation modeling (SEM) was applied, which represents the relationships and critical paths between the factors. A total of 219 half-structured deep interviews [78] were held in the local language with a conversation time ranging from 20-30 min. This included enumerators consisting of three researchers and six Ph.D. students performing interviews at different time stages, 3 h per each group (a senior and two students) daily (during the fair's working hours, 10-19 h). Each group had to mark the interviewees on the specially prepared list, which was transmitted to prevent overlapping. The interviews were conducted in the period February 22-25, 2018 at the International Belgrade Tourism Fair. The fair is considered one of the most important tourism events in Southeastern Europe and a gathering point for tourism providers at international and national levels. So far, various aspects of such fairs have been examined by scholars [79][80][81][82][83].
The interviews were undertaken by open-ended questions allowing the respondents to elaborate a freely structured discourse about the proposed topics, with minimal intervention to guide the process and perform quantification of responses. Before entering the interviewing process, a protocol was prepared. Piloting was performed to ensure the validity, clarity, and layout of the protocol. This also allowed the identification of possible omissions, irrelevant items, and determination of the time needed to finish the interviewing [84]. It was comprised of the following sections: Section 1: Introduction. The research aim and the respondents' critical role in providing firsthand data were briefly explained.
Section 2: Perception (gathering quantitative data during the interview). A set of questions were asked to evaluate the policy with regard to socio-cultural, environmental and economic impacts (Figure 1). It comprised 12 selected ETIS sustainable indicators, as a sufficient base to assess the A total of 219 half-structured deep interviews [78] were held in the local language with a conversation time ranging from 20-30 min. This included enumerators consisting of three researchers and six Ph.D. students performing interviews at different time stages, 3 h per each group (a senior and two students) daily (during the fair's working hours, 10-19 h). Each group had to mark the interviewees on the specially prepared list, which was transmitted to prevent overlapping. The interviews were conducted in the period February 22-25, 2018 at the International Belgrade Tourism Fair. The fair is considered one of the most important tourism events in Southeastern Europe and a gathering point for tourism providers at international and national levels. So far, various aspects of such fairs have been examined by scholars [79][80][81][82][83].
The interviews were undertaken by open-ended questions allowing the respondents to elaborate a freely structured discourse about the proposed topics, with minimal intervention to guide the process and perform quantification of responses. Before entering the interviewing process, a protocol was prepared. Piloting was performed to ensure the validity, clarity, and layout of the protocol. This also allowed the identification of possible omissions, irrelevant items, and determination of the time needed to finish the interviewing [84]. It was comprised of the following sections: Section 1: Introduction. The research aim and the respondents' critical role in providing first-hand data were briefly explained.
Section 2: Perception (gathering quantitative data during the interview). A set of questions were asked to evaluate the policy with regard to socio-cultural, environmental and economic impacts (Figure 1). It comprised 12 selected ETIS sustainable indicators, as a sufficient base to assess the perception of policy enablers on revealing perceived sustainability level of tourist destinations [85]. The balanced number of driving forces, impact and response for all three basic sustainability levels was introduced. Neutrally phrased items were used to minimize ambiguity in interpretation [61,62]. Section 3: Enablers' policy and challenges (gathering qualitative data during the interview). The aim was to explore the challenges and the necessity of reform of tourism development in the destination. Section 4: Interviewee data (Table 3). During the interviews, full notes were carefully taken and respondents were invited to describe their perception of the current status of sustainability of tourism destination. By choosing from a five-point Likert Scale (1 = strongly disagree to 5 = strongly agree) quantitative data were collected on the degree at which each interviewee evaluates the three sustainability pillars. Collected data were transferred and processed in SPSS 24.0. The research applied exploratory factor analysis (EFA) on 12 ETIS indicators to identify coherent factors that represent the underlying dimension. A principal axis factor with an oblique rotation (Promax) was chosen to accommodate the possible correlation among factors. Structural equation modeling (critical path analysis model) was applied to the sample of 219 respondents as the fully appropriate sample size [86][87][88]. The model represents the relationships between the factors within the socio-cultural, environmental and economic impacts in Serbian tourist destinations.
After collecting the quantitative data, the interview protocol consisted of another consolidated set of direct questions related to tourism development challenges. Qualitative data were also collected, as interviewees were asked to briefly explain their insights about the broad spectrum of policy issues. The objective was to determine their first-hand perception of policy perspectives on reform challenges and the necessity of intervention in the current tourism development agenda at a local level. Respondents were also asked to suggest the inclusion of any missed but relevant aspect in terms of tourism policy reform. The sentences they used, repetition, and their vigor of expression, led to Sustainability 2020, 12, 3491 7 of 16 overall expert judgment. Subjective assessment enabled concise summarization and comprehensive compilation of the judicial sentences and empirical generalization of findings and conclusion.
Following the interviews, content analysis of the existing strategic tourism development documents was conducted. The aim was to reliably detect whether they properly address the sustainability issues typically identified by the respondents and systematically and objectively identify any possible inferences [89]. As sources were used national strategic planning documents (National Strategy on Sustainable Development [64] and the Strategy of Tourism Development [65]), regional development plans, tourist destinations' master plans, and municipal tourism development plans. They serve as a basis on which many decisions are made for tourist destinations. An assessment was carried out based on the extent to which existing strategic documents addressed issues of sustainability concern to policymakers, and how frequently they referred to the topics raised by the interviewees. Table 3 presents the full data of the interviewees' profiles. The target group consisted of representatives at all levels of tourism policy organizations: local (79%), regional (8.4%), national (10.9%) and international (1.7%). They were identified as the main policymakers for fostering an environment for sustainable development of tourist destinations. The respondents were managers (35.3%) and employees (64.7%) of public (85.6%) and private organizations (14.4%) retaining a comprehensive image of the tourism development process in Serbia. Specifically, they worked in research centers and universities (4.2%), municipal institutions such as tourist organizations and offices (66.4%), hotels and other establishments (15.1%) and cultural and other associations (14.3%). The respondents came from 79 municipalities, covering about 60% of all local tourist organizations in Serbia. There was strict domination of females (64.4%) and highly educated respondents (87.3% with university diploma). Almost half of the respondents (49.2%) were between 36-60 years old, followed by those aged 18-45 years (46.6%), and there were only 4.2% older than 60.

Results
To explore the critical factors affecting the level of sustainability of tourist destinations in Serbia, respondents were invited to rate their level of agreement with sustainability indicators. Based on EFA, Table 4 presents the measurement variables for each impact factor in the form of a brief item providing sufficient internal consistency. A principal axis factoring was conducted with Promax rotation to determine the dimensionality of indicators. The total variance explained by three distinctive dimensions was 51.562%, being moderate enough. This is satisfactory, particularly in tourism studies where information is often less precise [90]. The overall Cronbach's alpha value of the indicators was 0.83, which is above the suggested benchmark of 0.6 [91]. The Kaiser-Meyer-Olkin value of sample adequacy was 0.634, being classified as a mediocre [90,92]. Bartlett's test is significant (p < 0.05) indicating the factor analysis is appropriate.
Socio-cultural sustainability indicators show a Cronbach's alpha value of 0.776 and explain 45.265% of the total variance. This impact represents two factors (Table 2, numbers F1 and F2) and both dimensions have high mean values. Each feature was set for further sub-dimensions. Thus, the first factor of the "Socio-cultural environment" has a Cronbach's alpha of 0.744 and a mean of 3.68 and consists of three items (social equity, authenticity of the destination, and cultural richness). The second socio-economic factor, "services", has a notably high Cronbach's alpha of 0.807 and a mean of 3.32, and consists of two items (transport services and communal services).
The second dimension, "environmental sustainability", and the third dimension, "economic sustainability", reflect with just one factor. The environmental sustainability produces a Cronbach's alpha of 0.882 and explains 55.463% of the total variance; the mean value is 3.16, and it consists of two items (natural resources of the destination and local community involvement in environmental protection). Economic sustainability includes three items (economic viability, employment quality, and local prosperity). This explains 53.959% of the total variance, with a high Cronbach's alpha value of 0.832, but the lowest mean value, 2.76. The policy enablers dimension records a high mean value of   Figure 2 presents the path analysis model indicating the relationships between the factors within the socio-cultural, environmental and economic impacts in Serbian tourist destinations. Some relations may be easily misinterpreted if respondents' answers are not properly addressed. Although it is logical to expect that transport and communal services may produce positive economic effects, here it is not the case. However, the respondents' distribution on the issue addressing the economic impacts explains the negative correlation. Namely, a substantial number of respondents expressed neutral perceptions on employment quality assessment, vis-à-vis the largest number of negative impressions concerning local prosperity issues. Similarly, one may explain the policy enablers' correlations. Questions concerning monitoring and managing of the sustainability levels at a destination also recorded mostly neutral statements. A negative assessment of 38.3% was evidenced in the case of evaluating the monitoring process, and 38.9% for assessing the management aspect of sustainability at destinations. Table 5 presents the goodness-of-fit measures. Accordingly, the model fit was found very satisfactory, since all fit indices were above the cut-points [90]. The chi-square is significant, and, in comparison with the sample size, the ratio χ 2 /df has a value lower than 5. Both CFI and IFI are above 0.9. RMSEA is slightly over 0.05, and SRMR is well below 0.8.  Table 5 presents the goodness-of-fit measures. Accordingly, the model fit was found very satisfactory, since all fit indices were above the cut-points [90]. The chi-square is significant, and, in comparison with the sample size, the ratio χ 2 /df has a value lower than 5. Both CFI and IFI are above 0.9. RMSEA is slightly over 0.05, and SRMR is well below 0.8.

Findings and Discussion
The research findings are elaborated in a two-fold manner. Firstly, the study assessed the policy perspective concerning the level of perceived sustainability of tourist destinations in Serbia. Secondly, upon the scholarly research approach, the study found many new insights for reforming current tourism development as well as some strategic challenges. Assessing possible factors affecting the level of sustainability of tourist destinations in Serbia by policy enablers revealed that socio-cultural impacts are perceived as the most beneficial. Sociocultural aspects like authenticity and uniqueness of destination act as the most relevant factors for sustainable development. As argued in [93], the cultural image often mediates environmental and economic perceptions at the destination level. Tourism policymakers outline that Serbian tourist destinations should focus on cultural values as an input of harmony, originality, and embrace of opposites, as argued by [94]. However, appropriate attention must be placed on the fact that cultural sensitiveness of tourist destinations calls for consistent monitoring. This also stands for social equity and cultural richness.
Surprisingly, the environmental factor was identified as having a medium impact for sustainability, unlike the notation in strategic documents, where the sustainable use of natural resources is strongly emphasized [65]. The ecological setting is found to be extremely fragile and sensitive [95], so the environmental sustainability (physical integrity, diversity, resource efficiency,

Findings and Discussion
The research findings are elaborated in a two-fold manner. Firstly, the study assessed the policy perspective concerning the level of perceived sustainability of tourist destinations in Serbia. Secondly, upon the scholarly research approach, the study found many new insights for reforming current tourism development as well as some strategic challenges. Assessing possible factors affecting the level of sustainability of tourist destinations in Serbia by policy enablers revealed that socio-cultural impacts are perceived as the most beneficial. Socio-cultural aspects like authenticity and uniqueness of destination act as the most relevant factors for sustainable development. As argued in [93], the cultural image often mediates environmental and economic perceptions at the destination level. Tourism policymakers outline that Serbian tourist destinations should focus on cultural values as an input of harmony, originality, and embrace of opposites, as argued by [94]. However, appropriate attention must be placed on the fact that cultural sensitiveness of tourist destinations calls for consistent monitoring. This also stands for social equity and cultural richness.
Surprisingly, the environmental factor was identified as having a medium impact for sustainability, unlike the notation in strategic documents, where the sustainable use of natural resources is strongly emphasized [65]. The ecological setting is found to be extremely fragile and sensitive [95], so the environmental sustainability (physical integrity, diversity, resource efficiency, environmental purity) was found hard to be perceived as the leading factor. Furthermore, the interviewed policymakers have recognized that environmental issues can be properly addressed only at higher development levels. Namely, tourism development in most destinations in Serbia is still small-scale and directly associated with socio-cultural factors and limited infrastructural capacities.
Although the dynamic economic environment makes it important to conduct monitoring of economic sustainability (employment, viability, local prosperity), policy perception on this issue has not researched the tipping point. Respondents indicate that policies are still primarily focused on issues related to infrastructure, product design, and marketing, and far less on supporting economic viability and facilitating local prosperity. This may jeopardize the wellbeing and livelihood of locals [96]. Therefore, it is essential to provide economic benefits to ensure locals' motivation to support tourism activities and preserve the destination's natural and cultural environment [24,51,97].
These categories are standardized and emerge as basic sustainable tourism principles, relevant to the destination's development. Consequently, these organizations are mostly concerned with planning for the present and future. However, such perceptions should be taken as personal and conceptual since what is perceived as sustainable practice differs between people and locations [98]. Since the parent theme was sustainable development, policy enablers highlighted the issue of re-shaping strategic documents to achieve access to sustainability. Even more, a concern that current tourism is focused solely on maintaining the number of tourists without taking care of responsible controlling has been raised. Tourism is commonly perceived to be on a maintainable level, although sometimes poor in quality, leading to a perception that support and coordination at all levels of policymaking are lacking. There is also a significant discrepancy in attitudes on prioritizing actions to improve the competitive position of Serbia in the international tourism market between the private and public sectors [23].
There is a general lack of cooperation between institutions and a reduced level of consolidation of different development goals, plans, and projects. Coordinated actions of defined stakeholders are missing, as they frequently exhibit a competitive rather than cooperative attitude, which is regarded the main obstacle in reaching sustainable development goals [22,99]. The role of local communities in the decision-making process is still extremely marginalized in Serbia, affecting perceived sustainability. Understanding the policy perspective allows current developing strategies to be assessed and re-shaped for their effectiveness and relevance to be developed. The qualitative analysis suggests changes in the policy context in a way to better embrace the key principles of sustainability [100]. The findings indicate a common belief that currently tourist destinations in Serbia are managed in a maintainable rather than in a sustainable manner. This means tourism is not operating at its optimum level, which flings a shadow of pessimism about the possibility to achieve sustainable grounds. As increasing tourist numbers in the destination remains an everlasting strategic goal, it simply confronts the sustainability principles. It was uncovered that, currently, policymakers are focused on sustaining some partial elements necessary for tourism development (such as ambient, authenticity, services, etc.), hence contributing merely to maintain the environmental quality [101,102]. This concept stands and works only in the short-term, unlike sustainability which represents a long-term, proactive and holistic approach [103]. This requires a change in perception, since sustainability no longer represents a strictly ecological concern (as in the case of strategic documents), but rather tackles a range of environmental, social, economic and other issues.
When comparing the results of content analysis of strategic tourism documents and personal perceptions of respondents, some overall convergences and divergences appeared. In terms of similarities, the same general perception that tourism in Serbia offers numerous benefits for tourist destinations and consequently should be positively acknowledged was uncovered. Similarities were also revealed in expressions of distress about the process of monitoring tourism product quality. Yet, rather than prevailing perceptions, several differences were noted, and a slight deviation occurred. Since tourism development documents typically reflect the broad concerns, the results suggest that they appeared to be less concerned with achieving sustainability than the interviewed policymakers. Namely, the documents contain directions focused on gaining positive impacts, omitting the essential elements of sustainability. Hence, they pose many so-called 'strategic areas of intervention', which were determined as primary concerns for enabling tourism growth. As such, current strategic documents lack the substantial element of the main definition of sustainability-enhancing local opportunities for the future [85]. This represents the main concern of policymakers when interviewed in person.
To summarize, the content analysis illustrated that current development plans and policies did not reflect real policy enablers' perceptions, but rather reflect those for just supporting maintainable tourism. The integral development component is missing as a key factor in reaching sustainability.
Ultimately, such a maintainable pattern may result in almost immediate positive tourism effects. However, sustainability will not exist until it is managed in such a way that differs from general policy directions [104]. This means that reforming current policy orientation is inevitable, which will lead to the inclusion of a broader perception as a crucial advantage in understanding and practicing sustainability. Indeed, until perceptions are thoroughly incorporated into strategic documents, management and monitoring of resources in tourist destinations in Serbia may continue to be perceived as unsustainable. This means tourism will most likely continue its development process without reaching general sustainability goals. As such, it may inevitably lead to exploitation and eventually deterioration of destinations and local resources.

Conclusions
This study examined the perceptions of policy enablers and explored the main challenges for tourist destinations in terms of sustainability. It has found that socio-cultural impacts are perceived as important for achieving sustainability when developing tourist destinations in Serbia. It also suggested a model that presents the relationship between factors within socio-cultural, environmental and economic impacts. It assists in monitoring and managing tourism activities and their impacts. As the model is developed in the case of Serbian tourist destinations, every generalization of the proposed model must consider that issues of sustainable development may vary from one place to another. There is a need to formulate place-specific policies with the ability to recognize the particular context of sustainability at the local level [56,105]. Implementing this model provides a possibility for managers and policy enablers to detect sustainability problems in a given tourist destination. The model also assists comprehension of how to initiate and carry out informed decisions with the aim of ensuring the destination's sustainability [37]. In the absence of such a framework, it would be challenging to identify issues and areas of intervention, and eventually duplicate efforts and waste resources. This enables a much smoother way for decision-makers to perceive the interconnection between the factors of influence and prioritize the action areas. As such, policymakers can be proactive in identifying problems and bridge the gap in due time.
The research confirmed that tourist destinations in Serbia need to re-shape their development plans and policies. As noted by [50], the accent should be on guaranteeing the social sustainability of the destination, unlike current policies that are missing that element. Thus, although it is declared for strategic documents that they foster tourism development by contributing to its sustainability, it was confirmed that they do not provide a broader picture. Conversely, such plans and documents manage the status quo to keep up with short-term impacts, staying focused predominantly on the quality of the product. Such an approach is increasing the risk of inappropriate monitoring and management at the destination level.
Several limitations were noted for this research, which may be addressed in some future work. Initially, data collection was performed during a tourism fair at an extremely busy time, so the perception of respondents might be a bit neglected. Second, the interview involved a rather limited set of sustainable indicators, opening the possibility for further expansion. Third, the sample was taken based on convenience sampling, so probability sampling techniques may be further introduced. Fourth, the study explored the case of Serbia and provides the most effective 'micro' solution to what remains essentially a 'macro' problem. Ultimately, the research departed from the conventional triple bottom line of sustainability, so some additional dimensions of sustainability might be included. Adding the aspect of institutional sustainability may broaden understandings on local planning policy, local-oriented control policy, political participation, political support, etc. The total variance explained may also be improved beyond the current moderate level of 51.562%. Nevertheless, the study presents a broad context of tourist destinations' sustainability and enables a better understanding of the current policy level attitude.