Indicators for Assessing Sustainability in Mediterranean Tourism Destinations: A Systematic Review

Abstract

This study presents a systematic critical review of 91 peer-reviewed publications published between 2000 and 2024, examining the sustainability of Mediterranean tourism destinations through indicator-based frameworks. Using the Scopus database (Elsevier) and PRISMA-based screening, the review coded studies by methodological approach, indicator type, sustainability dimension, stakeholder involvement, and data source. Quantitative and mixed-methods designs dominated the corpus, together accounting for 90.1% of the reviewed studies, while geographical coverage was highly concentrated in Spain (52.7%), Greece (14.3%), and Italy (13.2%), which jointly represented 80.2% of the corpus. The literature also expanded markedly over time, from 8 studies (8.8%) in 2003–2010 to 39 studies (42.9%) in 2021–2024. Dimensional analysis showed strong emphasis on economic and environmental sustainability assessment, addressed in 92.3% and 91.2% of studies respectively, whereas cultural sustainability received attention in only 23.1% of the corpus. These findings highlight persistent problems of geographic imbalance, limited standardisation, and insufficient multidimensional integration in Mediterranean tourism sustainability assessment. In response, the study proposes the Mediterranean Sustainability Assessment Framework (MSAF), an appraisal-oriented framework for evaluating and improving destination-level sustainability indicator systems in terms of dimensional completeness, methodological pluralism, and contextual embeddedness.

1. Introduction

Sustainability in tourism has evolved through multiple theoretical and policy-oriented interpretations. Sustainable tourism has been defined as tourism development that can continue without degrading the human and natural environment, while broader policy frameworks emphasise the balanced fulfilment of economic, social, aesthetic, and ecological needs [1,2]. These approaches align with the Triple Bottom Line and ESG (Environmental, Social and Governance) perspectives, both of which underscore the need for measurable and comparable tools for destination management [3,4]. In this context, sustainability indicators play a central role by translating broad principles into operational forms of monitoring, evaluation, and policy support [5].

International policy and assessment frameworks, including the United Nations Sustainable Development Goals (SDGs), the sustainable tourism indicators (STIs), and the European Tourism Indicator System (ETIS), have contributed to the formalisation of indicator-based approaches to tourism sustainability assessment and have encouraged greater standardisation in destination monitoring [6]. Previous reviews (

Table 1. Positioning of the Present Review against Related Review Studies.

Study	Review Type	Main Focus	Scope	Main Contribution	Limitations Relative to the Present Study
Torres-Delgado A, & Saarinen J. (2017) [7]	Literature review	Role, characteristics, and challenges of sustainability indicators in tourism development and planning	General/non-region-specific	Clarifies the conceptual role of indicators and distinguishes between indicator sets and indices	Not Mediterranean-specific; not a systematic critical mapping of destination-level studies; does not provide a region-focused empirical synthesis
Miller, G., & Torres-Delgado (2023) [11]	State-of-the-art review	Key tensions in measuring sustainable tourism, including measurement purpose, scale, participation, and policy relevance	General/non-region-specific	Highlights conceptual and methodological tensions in sustainable tourism measurement	Broad conceptual discussion; not Mediterranean-focused; does not systematically analyse a defined regional corpus
Rasoolimanesh, S. et al. (2023) [12]	Systematic scoping review	Sustainable tourism indicators in relation to the SDGs, governance, stakeholders, and subjective/objective indicators	General/international	Provides a structured review of STI research and identifies under-attention to governance and SDG alignment	Not Mediterranean-specific; emphasis is broader STI scholarship rather than a regional destination-focused corpus
Marinello, S., et al. (2023) [13]	Critical review	Evaluation and monitoring of sustainable tourism through indicator sets	General/destination-oriented	Reviews 104 papers and examines how indicator use varies by destination type and time period	Not Mediterranean-specific; does not focus on Mediterranean territorial patterns, regional bias, or a Mediterranean-specific assessment framework
Kristjánsdóttir, K. et al. (2018) [14]	Systematic literature review	Integrated sustainability indicators for tourism, with emphasis on methodological approaches	General/interdisciplinary	Highlights integrated and multi-level approaches, methodological innovation, and dynamic views of sustainability	Focuses specifically on integrated indicators rather than the broader field of indicator-based sustainability assessment in Mediterranean destinations
Vukadin IM et al. (2020) [15]	Review and evaluation	International systems of tourism sustainability indicators, especially UNWTO and ETIS	Framework/system level	Reviews major international indicator systems and identifies confusion caused by proliferating frameworks	Focuses on formal indicator systems rather than empirical review of destination studies; not Mediterranean-specific
Spencer, D. M., & Sargeant, E. L. (2024) [16]	Critical review based on systematic search	Indicators for measuring tourism sustainability at cultural heritage sites	Site-specific	Identifies methodological weaknesses in indicator reliability, validity, weighting, and long-term monitoring	Narrow thematic scope; centred on cultural heritage sites rather than Mediterranean tourism destinations more broadly
Gkarane, Sofia et al. (2024) [10]	Selective literature review	Emerging trends and future directions in Mediterranean coastal tourism	Mediterranean coastal tourism	Provides an overview of recent Mediterranean coastal tourism trends and future directions	Selective rather than systematic; coastal tourism focus; not specifically centred on sustainability indicator frameworks
Present study	Systematic critical review	Sustainability indicators in Mediterranean tourism destinations	Mediterranean region; 91 Scopus-indexed studies identified through PRISMA-based screening	Provides a region-specific critical synthesis of methodological approaches, indicator typologies, sustainability dimensions, geographic coverage, and alignment with broader sustainability frameworks, and proposes the MSAF as a diagnostic and revision-oriented framework	—

) have confirmed the value of such indicators, but they have also identified recurring weaknesses, including limited standardisation, insufficient stakeholder engagement, and an imbalance favouring environmental assessment over social and governance dimensions [7,8]. More recent studies have further stressed the need for context-sensitive and participatory approaches, especially in rural, cultural heritage, and coastal tourism settings [9,10].

The Mediterranean basin (Figure 1) constitutes a particularly important context for such analysis. It combines high environmental vulnerability, strong tourism dependence, marked seasonality, and complex pressures on cultural heritage and local governance [17]. These characteristics create a need for indicator frameworks capable of capturing ecological fragility, socio-economic dependence, and destination-specific management challenges.

To address these gaps, this present study conducts a systematic critical analysis of 91 studies on sustainability indicators in Mediterranean tourism destinations, selected through the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) screening protocol [18]. It examines methodological patterns, indicator typologies, dimensional representation, geographic coverage, and alignment with broader sustainability frameworks, while identifying barriers to more standardised and operational assessment models.

As a critical review, this study does not aim merely to catalogue published findings, but to identify recurrent conceptual, methodological, and geographical limitations in the existing body of research and to interpret their implications for sustainability assessment in Mediterranean tourism destinations. Accordingly, the analysis focuses not only on what indicators have been used, but also on how sustainability has been operationalised, which dimensions have been prioritised or neglected, and where important weaknesses remain in relation to contextual sensitivity, comparability, and stakeholder inclusion. The review is guided by four research questions:

• RQ1. What methodological approaches dominate the assessment of sustainability indicators in Mediterranean tourism destinations?
• RQ2. How are sustainability dimensions and indicator types represented across the reviewed literature?
• RQ3. What geographic and thematic patterns characterise the existing body of research?
• RQ4. What major gaps and limitations emerge from the literature, and how can these inform the development of more integrated assessment frameworks?

Building on these findings, the study proposes the Mediterranean Sustainability Assessment Framework (MSAF), which organises assessment capacity around dimensional completeness [19], methodological pluralism, and contextual embeddedness. Rather than merely restating corpus-level weaknesses, the MSAF translates them into a framework that can be used to identify omissions, assess methodological balance, and guide the revision of destination-level indicator systems.

2. Materials and Methods

This research employs a systematic literature review following PRISMA 2020 guidelines, combining systematic review procedures with qualitative thematic synthesis and descriptive bibliometric mapping. PRISMA 2020 provides updated guidance for the transparent reporting of how studies are identified, selected, appraised, and synthesised in systematic reviews. The review was reported in accordance with the PRISMA statement [18] and the PRISMA 2020 Checklist [20]. It was not prospectively registered, and no publicly accessible protocol was prepared. The dual approach enables identification of quantitative patterns in publication trends, geographic distribution, and methodological preferences, while simultaneously capturing qualitative insights regarding theoretical frameworks and practical applications. Scopus was selected as the primary database for its extensive coverage of peer-reviewed literature in environmental science, tourism studies, and sustainability research, and for the consistency of its indexing protocols—essential for reproducibility. The selected database was chosen because it provides broad coverage of peer-reviewed literature relevant to the topic under examination and allows the application of a transparent and reproducible search strategy. The use of a single database also facilitated consistency in screening, metadata handling, and duplicate control. Nevertheless, we acknowledge that additional databases might have retrieved further relevant studies, and this limitation is now stated explicitly in the manuscript. The temporal scope spans 2000 to 2024, capturing over two decades of evolution in sustainability indicator research.

The systematic search used four keyword groups: (indicator OR indicators OR index OR indices) AND sustainability AND tourism AND destination, applied to titles, abstracts, and keywords, yielding 415 publications. The search keywords were selected through an iterative process designed to reflect the conceptual scope of the review. Initial terms were derived from the core concepts of the study topic, after which the search string was refined by checking recurring terminology used in relevant publications retrieved during preliminary screening. This process allowed the inclusion of close variants and related expressions and reduced the risk of excluding relevant studies because of terminological differences. To improve search completeness, the final keyword set was reviewed against the terminology used in the studies included in the final dataset. The adequacy of the search strategy was therefore assessed not only by the initial retrieval results but also by the presence in the final sample of studies that were clearly relevant to the review objective. Following removal of 28 non-English language studies, 66 studies with irrelevant subject matter, and 230 studies failing additional eligibility criteria (duplicates, non-Mediterranean geographic scope, absence of explicit sustainability indicators, and non-peer-reviewed materials), the final corpus comprised 91 studies (Figure 2). These 91 studies refer to the final corpus included in the systematic review and qualitative synthesis, whereas the full reference list also includes conceptual, methodological, and contextual sources cited to frame the analysis. A full bibliographic overview of the 91 studies included in the qualitative synthesis is provided in Table S2 in the Supplementary Material [15,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110]. The PRISMA flow diagram was prepared using the PRISMA2020 Shiny app.

Inclusion required empirical application of sustainability indicators in Mediterranean tourism contexts—coastal, island, urban, rural, or mixed—addressing at least one recognised sustainability dimension and demonstrating practical implementation rather than purely theoretical discussion. Geographic eligibility was determined by a three-tier inclusion criteria framework applied consistently during the screening phase. Studies were included if their destination country: (i) physically borders the Mediterranean Sea (primary criterion); (ii) is formally recognised as a Mediterranean state by a supranational authority, including the Barcelona Convention, the Union for the Mediterranean, or the WestMED Initiative (secondary criterion); or (iii) demonstrates documented socio-cultural, environmental, and tourism-structural affinity with Mediterranean basin states, as evidenced in peer-reviewed literature (tertiary criterion). A country satisfying any two of the three criteria was deemed eligible for inclusion. This framework was established prior to screening and applied uniformly to all candidate studies.

The qualitative component of the review was informed by thematic synthesis, which involves the systematic coding of textual material, the development of descriptive themes, and the generation of higher-order analytical themes. This approach was considered appropriate because it allows the review to remain closely grounded in the included studies while also supporting interpretive synthesis beyond simple description [111]. A comprehensive coding framework was developed through iterative design and pilot testing, recording bibliographic, geographic, methodological, and indicator characteristics, as well as stakeholder engagement patterns and data sources. To strengthen coding reliability, a proportion of the included studies was independently verified by the second author. Specifically, all of the 91 studies were double-coded in order to assess the consistency of coding across methodological approaches, sustainability dimensions, indicator types, stakeholder involvement, and data sources. Any disagreements were reviewed jointly by the authors and resolved through discussion until consensus was reached, after which the coding scheme was finalised for the full analysis. Indicator coding was conducted through a structured multi-code scheme that classified each study according to the sustainability dimensions addressed, the types of indicators used, the methodological approach adopted, the degree of stakeholder involvement, and the principal data sources. Multiple coding was permitted where a study addressed more than one dimension or methodological category. The variables included in the statistical analysis were selected from this coding framework because they represented the main comparative characteristics of the review corpus and allowed the identification of relationships, group differences, and temporal patterns relevant to the research questions.

Quality assessment employed a modified evaluation tool adapted for indicator-based sustainability research, evaluating clarity of objectives, appropriateness of indicator selection, adequacy of data sources, transparency of analytical procedures, and validity of conclusions. Validation relied on methodological triangulation, code-recode checks in temporally separated rounds, a detailed audit trail, and sensitivity analyses varying inclusion thresholds and thematic grouping rules to test the stability of findings under alternative assumptions. Because several variables in the review dataset were categorical or ordinal and the data did not meet the assumptions required for parametric testing, non-parametric procedures were used to examine associations, group differences, and temporal patterns [112]. Because several variables in the review dataset were categorical or ordinal and did not meet the assumptions required for parametric testing, non-parametric statistical tests were used to examine associations, group differences, and temporal patterns. Chi-square and Fisher’s exact test were used to assess relationships between categorical variables, Mann–Whitney U and Kruskal–Wallis to compare independent groups, and Spearman correlation to examine monotonic associations involving ranked or non-normally distributed variables. Risk of bias due to missing results in the synthesis was not formally assessed. Nevertheless, language restrictions, database selection, and publication-type exclusions may have introduced reporting bias and affected the comprehensiveness of the evidence base. These tests were used to examine whether observable patterns within the review corpus were statistically meaningful and were not intended to imply causal relationships between methodological or thematic features of the included studies [112]. Statistical analyses were performed using IBM SPSS Statistics, version 29.

Visualisation was used as a complementary analytical technique to support the descriptive and comparative interpretation of the review corpus. Specifically, time-series visualisation was used to examine publication trends over time, bar charts to compare the representation of sustainability dimensions across categories, geographic heatmaps to display the spatial distribution of studies, and Sankey diagrams to illustrate relationships between tourism contexts and methodological approaches. These visual tools were applied to enhance analytical clarity and to support the identification of temporal, spatial, and relational patterns within the dataset. Visualisations were produced using R, version 4.3.2. The substantive findings derived from these visualisations are presented in Section 3.

3. Results

To improve clarity, the Results Section is organised in relation to the four research questions. Section 3.2, Section 3.3 and Section 3.8 address RQ3 by examining the geographic, temporal, and thematic distribution of the reviewed literature. Section 3.4, Section 3.6 and Section 3.7 address RQ1 by analysing methodological approaches, technological integration, and the data sources and scales used in sustainability assessment. Section 3.5 and Section 3.9 address RQ2 by examining the representation of sustainability dimensions and stakeholder engagement patterns. Finally, Section 3.10 synthesises the principal strengths, weaknesses, and gaps emerging from the review and therefore contributes directly to RQ4.

3.1. Statistical Associations Across the Review Corpus

Table 2. Statistical Test Result Summary.

Test Type	Variables	Sample Size	Test Statistic	Additional Info	p-Value	Effect Size	Significance	Interpretation	Practical
Chi-square (χ2)	Method × Country	N = 91	χ2 = 26.181	df = 18	0.096	V = 0.379	Not sig.	No assoc. method–country	Method not geographic
Fisher’s Exact	Tech × Method	N = 91	OR = 2.567	95% CI: 1.02–6.45	0.047	Medium	Significant	Sig. assoc. tech–method	Mixed 2.6× more tech
Mann–Whitney U	Quant vs. Mixed	n = 40, n = 42	U = 652.5	Z = −1.74	0.083	r = 0.182	Not sig.	No diff. method complexity	Method not complexity
Kruskal–Wallis	Spain/Greece/Italy	n = 48/13/12	H = 0.14	df = 2	0.932	η2 = 0.002	Not sig.	No diff. across countries	Consistent across Med.
Spearman Corr.	Year × Complex.	N = 91	ρ = 0.025	95% CI: −0.18–0.23	0.816	Negligible	Not sig.	No temporal trend	Stable over time

summarises the statistical associations identified across the review corpus. Fisher’s exact test indicated that mixed-methods studies were significantly more likely to incorporate advanced technologies (odds ratio = 2.567, p = 0.047). By contrast, no significant differences were found in indicator complexity across methodological approaches (Mann–Whitney U = 652.5, p = 0.083) or across major Mediterranean countries (Kruskal–Wallis H = 0.140, p = 0.932), and no significant temporal trend in indicator sophistication was detected (Spearman r = 0.025, p = 0.816).

3.2. Geographic Distribution of Studies

Figure 3 shows the spatial distribution of the reviewed studies across Mediterranean countries.

Research on Mediterranean tourism sustainability is concentrated in a small number of countries, with Spain clearly dominating the evidence base, followed by Greece and Italy, while Portugal, Croatia, Turkey, and a small group of other countries remain much less represented. The distribution indicates that the literature is shaped not only by the geography of tourism pressure in the region but also by uneven research capacity across national academic contexts. As a result, the current evidence base is regionally uneven and centred on a limited set of Mediterranean destinations. The absence of France, Morocco, Algeria, and Egypt from the corpus is an empirical outcome of the systematic search, not an exclusion decision. No publication meeting all eligibility criteria was identified for these countries, despite their significance as Mediterranean tourism destinations. France’s absence may in part reflect the language eligibility criterion, which required publications to be in English, potentially excluding relevant French-language scholarship. The absence of North African countries—Morocco, Algeria, and Egypt—confirms the geographic bias identified as a systemic challenge of the field and constitutes an important gap in the reviewed corpus requiring attention in future research.

3.3. Temporal Evolution of Research

The temporal analysis (Figure 4) reveals distinct phases in research development across four periods: 8 studies in 2003–2010, 12 in 2011–2015, 32 in 2016–2020, and 39 in 2021–2024. The distribution indicates that research on sustainability indicators in Mediterranean tourism destinations expanded markedly after 2015.

Figure 4 shows the growth in publications on Mediterranean tourism sustainability research over the study period. The first phase represents the earliest stages of academic interest in sustainability indicators for Mediterranean tourism. This limited output reflects the lack of theoretical frameworks and methodological tools that could have supported more systematic approaches to sustainability assessment. The second phase signals the beginning of more systematic research approaches and the formation of more mature methodological frameworks. During this period, researchers began to develop more sophisticated measurement tools and to explore integrated approaches to the environmental, economic, and social dimensions of sustainability. The third phase showed significant acceleration driven by increasing policy attention and the recognition of sustainability challenges at the international level. This period was characterized by the maturation of methodological approaches and the incorporation of more complex analytical tools. The fourth and most productive phase marked an exponential expansion indicating both the maturation and the urgency of this research field. This period recorded the highest number of publications. The increase in publications coincided temporally with policy developments. The United Nations Sustainable Development Goals adopted in 2015 provided a global framework that sparked increased academic attention and created specific targets for integrating sustainability into the tourism sector. In parallel, the European Tourism Indicator System (ETIS) offered standardized methodologies for sustainability assessment, providing researchers and destination managers with practical tools for measuring and monitoring progress. In addition, the growing recognition of overtourism and carrying capacity issues in Mediterranean destinations further intensified research into innovative assessment methodologies. This temporal evolution simultaneously reflects the increasing complexity of sustainability assessment methodologies and the mounting urgency of addressing tourism impacts in the Mediterranean region. This urgency was particularly reinforced after high-profile cases of overtourism in destinations such as Barcelona, Venice, and Santorini, which raised awareness among both the academic community and policymakers of the need to develop more sophisticated and effective tools for monitoring and managing sustainability.

3.4. Methodological Approaches

It should be noted that methodological categories in this review are not mutually exclusive: a single study may employ two or more approaches concurrently—for instance, combining composite indices with GIS-based spatial analysis, or integrating quantitative indicator sets with qualitative Delphi panels. Consequently, the percentages reported in this section reflect the prevalence of each method across the 91 reviewed studies, not the proportion belonging to a single category. The sum of percentages therefore exceeds 100%, which is an expected and intentional feature of a multi-code classification framework [113].

Sankey diagram visualization (Figure 5) presents the distribution of methodological approaches across the reviewed studies. The reviewed literature is methodologically dominated by quantitative approaches, indicating a strong preference for measurement-driven assessment and cross-case comparability in the evaluation of tourism sustainability. Mixed-methods designs are also well represented, mainly where quantitative indicators are complemented by stakeholder-based or expert-informed techniques to support interpretation, weighting, or validation. By contrast, purely qualitative approaches remain marginal and are used largely in a supporting rather than leading role. Overall, these results show that Mediterranean tourism sustainability research continues to prioritise numerical robustness and operational applicability, while showing a gradual, but still secondary, move towards greater methodological pluralism and contextual sensitivity.

The quantitative emphasis aligns with the practical need for objective, comparable metrics that can inform policy decisions and enable benchmarking across destinations. However, this methodological bias may limit the capture of contextual nuances and stakeholder perspectives that are crucial for comprehensive sustainability assessment. An analysis of methodological techniques—acknowledging that most studies deploy more than one tool—reveals several prevalent approaches that frequently co-occur within the same study design. The methodological toolkit of the reviewed literature is centred on techniques that support aggregation, comparison, and operational decision-making across multiple dimensions of sustainability (Figure 6). Composite indicators, statistical analysis, and survey-based approaches form the core of this toolkit, showing a strong emphasis on structured measurement, stakeholder-informed evidence, and the production of comparable assessment results. Multi-criteria decision-making methods further reinforce this applied orientation by supporting prioritisation and weighting processes, while the use of GIS and spatial analysis indicates growing recognition that sustainability challenges in tourism destinations are also spatially differentiated. Overall, the pattern suggests a field that relies primarily on analytical tools designed to integrate complex indicator sets into policy-relevant and destination-specific assessment frameworks. This pattern is consistent with broader review-based concerns that sustainability assessment often privileges measurable and operationally comparable approaches, while leaving less room for context-sensitive and interpretive forms of analysis (Table 1).

3.5. Coverage of Sustainability Dimensions

The reviewed literature shows a clear imbalance in the treatment of sustainability dimensions (Figure 7), with economic and environmental aspects occupying the core of existing assessment frameworks. These results show that Mediterranean tourism research has prioritised dimensions that are more readily measurable and closely linked to destination performance and environmental pressure. By contrast, social and governance dimensions receive noticeably less systematic attention, while the cultural dimension remains particularly underrepresented. This uneven coverage indicates that current indicator-based approaches still fall short of capturing the full multidimensional character of sustainability in Mediterranean tourism destinations.

Environmental sustainability indicators coalesce around five interdependent domains that capture pressures, states, and responses across destination systems. Resource management remains foundational, with systematic tracking of water consumption per tourist-night, energy use intensity by accommodation type, and solid waste generation and diversion rates, thereby enabling evidence-based efficiency measures, circularity interventions, and demand-side management under peak-load conditions. Carrying capacity is operationalized through tourist density thresholds relative to resident populations and sensitive ecosystems, augmented by composite environmental pressure indices that integrate land-use conversion, infrastructure saturation, and habitat fragmentation to identify tipping points and inform visitor dispersion policies. Pollution assessment frameworks monitor ambient air pollutants (e.g., NOx, SO₂, and PM), coastal and inland water quality parameters (e.g., nutrients, BOD, and microbiological indicators), and noise levels in high-traffic corridors, with seasonal disaggregation to capture peak-period externalities and compliance gaps. Biodiversity conservation is gauged via coverage, connectivity, and management effectiveness of protected areas, complemented by ecosystem health indicators such as habitat condition scores and species abundance indices, and supported by visitor management instruments (e.g., zoning, quotas, and path design) to mitigate disturbance. Climate impact metrics bridge mitigation and adaptation by quantifying carbon footprints at destination and visitor levels, assessing progress on decarbonization (renewable integration, modal shift, and building retrofits), and documenting adaptation measures to heat stress, water scarcity, coastal erosion, and sea-level rise, including nature-based solutions that jointly enhance resilience and ecological integrity.

Economic sustainability indicators emphasize both the scale and quality of tourism-driven value creation, alongside the stability and inclusiveness of benefits. Tourism revenue is assessed through direct and indirect contributions to gross value added, complemented by multiplier analysis to capture upstream and downstream linkages and leakage diagnostics that reveal retention performance within local economies. Employment generation is measured in total and full-time-equivalent terms with attention to seasonal volatility, job quality, skills profiles, and career pathways, reflecting the sector’s capacity to provide stable and dignified work beyond peak months. Destination competitiveness is tracked using market share evolution, revenue per visitor and length of stay, tourist satisfaction indices, and repeat visitation rates, taken together as a composite signal of price–quality positioning, service performance, and brand equity. Seasonality analysis quantifies the temporal concentration of arrivals and receipts, evaluates infrastructure under-utilization outside peak periods, and appraises the effectiveness of diversification strategies (e.g., cultural, nature-based, and MICE tourism) in smoothing demand and stabilizing incomes. Finally, local economic integration indicators examine procurement shares from local suppliers, SME participation in tourism value chains, and cluster development around gastronomy, crafts, and creative industries, evidencing the depth of domestic linkages and the diffusion of benefits across sectors and territories.

Social sustainability indicators foreground the lived experience of residents and visitors, the safeguarding of heritage, and the fair distribution of benefits and burdens. Community well-being is assessed through resident satisfaction, perceived quality of life, and social cohesion metrics, with parallel attention to housing affordability, congestion, and access to essential services in tourism-intensive neighborhoods. Cultural preservation indicators encompass the conservation status of tangible and intangible heritage, authenticity maintenance in cultural offerings, and visitor management in sensitive cultural sites, ensuring that cultural capital is transmitted without commodification that erodes meaning. Social equity is addressed through distributional analyses of tourism’s gains and costs across demographic groups and neighborhoods, monitoring inclusive employment, accessibility, and affordability to avoid exclusion and displacement. Stakeholder participation is appraised via the breadth and depth of engagement in planning and monitoring, the co-creation of development scenarios, and the institutionalization of deliberative forums that strengthen legitimacy and adaptive learning.

Governance indicators, in turn, evaluate the coherence and effectiveness of policy frameworks, the integration of tourism into spatial and environmental planning, and the regulatory capacity to enforce standards; institutional capacity is reflected in staffing, data systems, monitoring, and inter-agency coordination, while stakeholder engagement mechanisms, transparency, and accountability are evidenced through open data portals, regular public reporting, and accessible grievance redress channels that foster trust and continuous improvement. The imbalance observed here reinforces earlier concerns in the literature that tourism sustainability assessment frameworks frequently give stronger weight to environmental and economic measurement than to social, governance, and cultural dimensions (Table 1).

3.6. Technological Integration

The reviewed literature shows selective rather than broad technological integration, with methodological innovation concentrated in a limited set of established tools (Figure 8). Artificial Intelligence (AI) and Machine Learning (ML), together with GIS and spatial analysis, form the main technological core of current assessment practice, indicating a growing interest in prediction, classification, and place-sensitive analysis. By contrast, Remote Sensing, IoT, and especially big data analytics remain only marginally incorporated, suggesting that the field has not yet fully operationalised the potential of high-frequency and data-intensive monitoring approaches. Overall, this pattern points to a transitional methodological stage in which sustainability assessment is moving beyond conventional techniques, but still shows more limited coverage of fully integrated and technologically advanced analytical frameworks. Figure 8 is based on 85 studies rather than the full corpus of 91 because six studies did not provide sufficient information for coding technological use, or did not include any explicit technological component relevant to this part of the analysis. These studies were therefore excluded from the technology-specific sub-analysis, while remaining part of the overall review corpus.

3.7. Data Sources and Scales

The reviewed literature relies on a strongly hybrid evidence base, combining primary and secondary data to balance contextual sensitivity with comparability across destinations (Figure 9). These results show that sustainability assessment in Mediterranean tourism is generally grounded in triangulation rather than in single-source designs, with purely desk-based or exclusively primary approaches remaining relatively uncommon. Primary data collection is used mainly to capture local conditions, stakeholder perceptions, and institutional dynamics that are not readily available in documentary sources, while secondary data provide the broader empirical and comparative foundation for assessment. Surveys, interviews, participatory workshops, and field measurements therefore function not simply as data-gathering tools, but as mechanisms for strengthening the validity, interpretability, and practical relevance of indicator-based sustainability analysis.

Assessment in the reviewed literature is oriented primarily towards the local and regional scales, where sustainability pressures, governance capacity, and data availability are most directly connected to destination management and policy implementation (Figure 10). This scale pattern suggests that the field is mainly concerned with producing context-sensitive and operationally relevant evidence rather than broad macro-level comparison. National-level assessments play a more limited role and are used mainly to support harmonisation and baseline-setting, while global-scale approaches remain marginal because cross-context standardisation is methodologically difficult and often weakens policy relevance. Overall, the dominance of sub-national scales reflects the place-specific character of Mediterranean tourism sustainability challenges and the corresponding need for actionable evidence at the level where interventions are designed and monitored.

3.8. Tourism Types Addressed

Coastal and beach tourism clearly dominates the research landscape, reflecting the centrality of the Mediterranean’s “sun, sea, and sand” model, its major economic weight, and the concentration of sustainability pressures in ecologically fragile coastal zones (Figure 11). Urban tourism also receives substantial attention, mainly in relation to overtourism, infrastructure strain, housing pressures, and resident displacement in major Mediterranean city destinations. Cultural and heritage tourism, together with mass tourism, further highlights the tension between preserving cultural assets and managing visitor volumes that may exceed local carrying capacity. By contrast, rural and nature-based tourism remain less studied despite their potential to redistribute tourism pressures and support more diversified development pathways. Most notably, island tourism remains significantly underrepresented, even though many Mediterranean islands face acute sustainability challenges linked to resource scarcity, waste management, seasonal population fluctuations, and ecosystem vulnerability.

3.9. Stakeholder Engagement

Stakeholder engagement in the reviewed literature is shaped primarily by institutional actors, with public authorities occupying the central role in regulation, data provision, and destination planning, and private companies contributing mainly through operational and investment-related influence (Figure 12). Academic experts also play an important part, particularly in indicator design and methodological structuring, while the involvement of residents and local communities remains present but still comparatively limited in relation to the participatory demands of sustainability assessment. Tourism organisations appear in a more secondary coordinating role, mainly supporting benchmarking and sectoral alignment. The weakest presence is that of NGOs and civil society, which points to a narrow participatory base and suggests that current assessment practices still underuse the potential contribution of advocacy, independent scrutiny, and broader co-production to more transparent and socially robust destination governance.

3.10. Key Strengths and Limitations

The application landscape of the reviewed literature is oriented primarily towards policy-making and governance, indicating that sustainability indicators are used chiefly to support public decision-making, monitoring, and the translation of evidence into destination strategies and regulatory action (Figure 13). A substantial share of the literature is also framed by broader sustainability assessment models, showing the importance of structured indicator systems for comparing destinations and organising trade-offs across sustainability dimensions. Urban and spatial planning constitute another major area of application, reflecting the need to address tourism pressures through land-use, mobility, and coastal management instruments. By contrast, tourism and destination management appear in a more operational and secondary role, while environmental management remains comparatively less developed despite the ecological vulnerability of many Mediterranean destinations.

The reviewed literature is dominated by empirical case-study research, indicating a strong orientation towards context-specific assessment and practical relevance in Mediterranean tourism destinations (Figure 14). Theoretical and conceptual frameworks are also present, but they are used mainly to structure applied analysis rather than to advance independent theory-building. Approaches that combine conceptual development with direct empirical validation remain relatively limited, pointing to a weaker tradition of iterative theory testing across cases. Overall, this pattern suggests a field that is methodologically well established in applied terms, but still offers scope for stronger conceptual synthesis, greater cross-case replication, and more cumulative analytical development.

The reviewed literature is characterised by strong empirical grounding and generally solid methodological practice, particularly through case-based validation, extensive use of primary data, and broad coverage of economic and environmental dimensions (Figure 15).

These features strengthen the practical relevance and internal credibility of the field, while the prominent role of public authorities also facilitates data access, regulatory alignment, and the uptake of findings in policy settings. At the same time, this profile reveals important limitations, including the weak integration of big-data approaches, the comparatively limited treatment of social and especially cultural dimensions, and the very restricted participation of civil society actors in assessment processes. In addition, the geographic concentration of the corpus in a narrow set of Mediterranean contexts constrains external validity and indicates the need for broader spatial replication and stronger cross-case synthesis.

These findings are broadly consistent with prior review studies cited in Table 1, which have also identified limited standardisation, uneven dimensional coverage, and insufficient stakeholder engagement, while the present review specifies how these weaknesses are expressed within Mediterranean destination research. The limited breadth and depth of stakeholder participation observed across the reviewed studies further suggests that many indicator systems remain managerially oriented rather than genuinely participatory in design and application (Table 1).

4. Discussion

Taken together, these findings do not simply extend the existing literature on tourism sustainability indicators, but sharpen several concerns already noted in previous review work, particularly the persistence of methodological concentration, uneven dimensional coverage, and insufficiently participatory assessment design (Table 1). The systematic review reveals a field undergoing rapid transformation and maturation, evidenced by the exponential growth in research output from 8 publications in the nascent phase (2003–2010) to 39 publications in the recent expansion period (2021–2024). This four-fold increase in research intensity over two decades reflects not merely academic interest but a fundamental shift in how Mediterranean destinations conceptualize and operationalize sustainability assessment.

The temporal pattern suggests that sustainability indicator research in Mediterranean tourism has evolved in close interaction with policy agendas, particularly where international frameworks created demand for more operational assessment tools. Rather than reflecting a purely theory-driven field, this development points to a largely applied and problem-oriented literature shaped by governance needs and by the increasing visibility of overtourism pressures in emblematic Mediterranean destinations. At the same time, such responsiveness may also indicate a predominantly reactive research agenda, with more limited emphasis on anticipatory approaches capable of addressing emerging sustainability risks before they become acute.

The strong geographic concentration of the literature narrows the evidentiary base on which wider Mediterranean conclusions can be drawn. Rather than simply showing where tourism activity and research capacity are strongest, this pattern points to a structurally uneven field of knowledge production that privileges European Mediterranean settings. As a result, region-wide sustainability frameworks risk being shaped by institutional, data, and governance conditions that are not representative of the basin as a whole. The limited inclusion of North African and Eastern Mediterranean contexts therefore weakens transferability and suggests that broader spatial coverage is necessary before more generalisable assessment models can be claimed.

The strong preference for quantitative approaches is not merely a stylistic tendency of the research community but reflects deeper structural pressures embedded in the political economy of destination management. Policymakers and destination management organisations operate under accountability frameworks that demand measurable, auditable performance indicators—a demand that has systematically incentivised composite indices and multi-criteria methods at the expense of participatory and interpretive approaches [19]. The consequence is a methodological monoculture that privileges what can be counted over what can be understood, producing indicator systems that are technically rigorous but epistemologically narrow. The moderate adoption of mixed-methods designs signals growing awareness of this limitation, yet the integration of qualitative insights frequently remains supplementary—used to validate or weight quantitative outputs—rather than constitutive of the analytical framework. This asymmetry matters: the social and cultural dimensions of sustainability involve power relations, place identity, and meaning-making processes that resist numerical reduction [114]. Until qualitative methods are afforded equal analytical status, indicator systems will continue to produce assessments that are comprehensive in appearance but partial in substance. The prevalence of survey-based research deserves particular critical attention. Whilst surveys generate valuable stakeholder data, the engagement they enable is predominantly extractive: respondents provide information but do not co-produce knowledge. This reproduces, at the methodological level, the same democratic deficit that governance indicators are meant to diagnose at the destination level. Advancing methodological pluralism therefore requires not only technical diversification but a normative reorientation toward participatory epistemologies. The dominance of quantitative approaches enhances comparability and operational usability, but it may also narrow the interpretive scope of sustainability assessment by favouring what is most easily measured over what is most contextually significant.

The near-universal coverage of economic and environmental dimensions reflects not their inherent importance but the path dependency of sustainability frameworks built on the Triple Bottom Line, which has historically privileged these two pillars whilst treating social and governance dimensions as secondary [19]. This is a structurally produced blind spot, not a random gap. Cultural heritage, whilst widely acknowledged as the primary driver of Mediterranean tourism demand, is systematically omitted because it resists the quantification logic that dominates the field—authenticity, cultural integrity, and the risk of commodification cannot be meaningfully captured through numeric proxies alone. This risk is particularly acute in rural and agritourism contexts, where cultural heritage and community identity constitute the primary tourism asset, yet remain the most vulnerable to commodification in the absence of participatory governance mechanisms [9]. Although rural tourism is not absent from the reviewed corpus, with eight of the 91 studies addressing rural areas, it remains comparatively limited within the broader Mediterranean sustainability literature. This suggests that rural and agritourism contexts have not yet received analytical attention proportionate to their significance for cultural heritage preservation, community identity, and territorially embedded development pathways. Recent work such as Mulita & Sefa (2025) [9] further reinforces the need for more context-sensitive sustainability assessment approaches tailored to Mediterranean rural destinations. The underrepresentation of governance indicators is equally consequential. Sustainability ultimately depends on institutional capacity, policy coherence, and legitimate participation in decision-making—precisely the variables that governance indicators are designed to capture. Their absence from over 40% of studies means that the field lacks the analytical tools to diagnose the institutional failures that perpetuate unsustainable tourism development. This finding aligns directly with the MSAF’s dimensional completeness axis: a framework that omits governance and cultural pillars cannot, by definition, produce a holistic sustainability assessment, regardless of its technical sophistication.

The substantial uptake of AI/ML techniques reflects genuine methodological progress, enabling pattern recognition and predictive modelling across complex, multidimensional indicator sets that exceed the capacity of conventional statistical tools. Yet the marginal adoption of big data analytics, remote sensing, and IoT technologies reveals a structural gap between what the field recognises as valuable and what it has the institutional capacity to implement. This is not primarily a methodological problem but an infrastructural one: the deployment of high-frequency, spatially granular data architectures requires data governance arrangements, interoperability standards, and technical capacity that most Mediterranean destination management organisations do not yet possess. The implication is that advancing technological integration in sustainability assessment requires institutional development in parallel with methodological innovation. Methodological convergence—linking AI/ML with GIS, remote sensing, and IoT data streams—will only produce policy-relevant outputs if the destinations intended to use them have the absorptive capacity to do so. This observation points directly to a governance gap that the MSAF’s contextual embeddedness axis is designed to address.

The dominance of public authorities in stakeholder engagement reflects the formal gatekeeping role of institutions in sustainability governance, but it also reveals a hierarchical pattern that has substantive consequences for assessment quality. The marginal participation of NGOs and civil society organisations means that advocacy perspectives, environmental protection priorities, and social justice concerns are structurally underrepresented in indicator design and validation. This is not merely a methodological limitation—it is a legitimacy deficit that undermines the social licence of sustainability initiatives in communities where residents experience the costs of tourism most acutely. The moderate engagement of local communities further suggests that current assessment practices remain insufficiently participatory for adaptive governance. Ostrom’s [114] socio-ecological systems framework argues that legitimate, adaptive resource governance requires the co-production of knowledge between institutional actors and affected communities. The stakeholder patterns observed in this corpus indicate that Mediterranean sustainability assessment has yet to internalise this principle at scale.

The predominance of local-scale assessments reflects the governance reality that most sustainability interventions are designed and implemented at the destination level. However, the limited attention to national and global scales produces a fragmentation problem: without standardised frameworks that enable cross-destination comparison, locally optimised indicator systems cannot generate the cumulative knowledge needed to inform regional or international policy coordination. The tension between contextual specificity and comparability is the central methodological challenge the field must resolve, and it is precisely what the MSAF’s methodological pluralism axis seeks to bridge. The systematic underrepresentation of island tourism is notable. Mediterranean islands face sustainability challenges—resource scarcity, waste management, seasonal population fluctuations, ecosystem fragility—that are qualitatively distinct from those of coastal or urban destinations and that are rendered invisible by indicator frameworks developed for continental contexts. Recent scholarship on emerging trends in Mediterranean coastal tourism further underscores the urgency of developing forward-looking, participatory indicator frameworks capable of anticipating—rather than merely documenting—the sustainability pressures that coastal destinations will face under conditions of accelerating climate change and shifting visitor demand patterns [10]. The absence of dedicated island frameworks is a gap that the field must treat as urgent, given the accelerating pace of climate-driven coastal and marine degradation across the Mediterranean archipelagos.

The diversity in indicator definitions, measurement methods, and aggregation approaches across the 91 reviewed studies demonstrates that convergence toward internationally recognised frameworks—STIs, ETIS, SDGs—remains incomplete and largely superficial. Studies cite these frameworks as reference points but rarely apply them with sufficient rigour to enable systematic benchmarking. The limited adoption of ESG-like accountability mechanisms is particularly notable: as sustainability reporting becomes increasingly institutionalised in corporate and investment contexts, destination-level assessments that lack comparable transparency and disclosure standards risk becoming peripheral to the policy and financing decisions that drive actual sustainability transitions. Strengthening alignment between destination sustainability assessment and ESG and SDG reporting architectures is therefore not merely an academic aspiration but a practical precondition for integrating Mediterranean tourism governance into the broader sustainable development agenda.

The Mediterranean Sustainability Assessment Framework (MSAF) was developed directly from the principal deficits identified in the reviewed literature. First, the marked imbalance across sustainability dimensions, particularly the underrepresentation of cultural and governance indicators relative to environmental and economic ones, informed the axis of dimensional completeness. Second, the strong dominance of quantitative approaches, together with the more limited use of qualitative and participatory methods, informed the axis of methodological pluralism. Third, the geographic concentration of studies in a small number of countries, the uneven thematic distribution of research, and the limited inclusion of broader stakeholder groups informed the axis of contextual embeddedness. Taken together, these patterns showed that existing assessment systems are often only partially comprehensive, methodologically narrow, and insufficiently adapted to destination-specific conditions, which is precisely the gap the MSAF is intended to diagnose. MSAF should be understood as complementary to, rather than a substitute for, established sustainability assessment frameworks such as TBL, PSR, and DPSIR. Whereas TBL emphasises the balanced consideration of core sustainability dimensions, and PSR/DPSIR provide structured causal logics for linking pressures, states, impacts, and responses, MSAF focuses specifically on the diagnostic evaluation of sustainability assessment systems themselves. Its added value lies in assessing whether destination-level indicator frameworks are sufficiently multidimensional, methodologically plural, and contextually embedded to capture the complexity of sustainability in Mediterranean tourism destinations.

The three systemic challenges identified in this review—heterogeneity and lack of standardisation, dimensional imbalance, and geographic and methodological bias—are not isolated empirical observations; they form a coherent theoretical pattern. Drawing on socio-ecological systems theory [114] and the multi-capital framework underpinning the SDGs, the MSAF reconceptualises indicator failure as a governance and epistemological problem, not merely a technical one [19]. Destinations that perform poorly on sustainability assessment do so because their indicator systems lack dimensional completeness (ignoring cultural and governance pillars) [19], methodological pluralism (over-relying on quantitative proxies at the expense of participatory validation), or contextual embeddedness (applying frameworks designed for Western European contexts to structurally different North African or Eastern Mediterranean settings). This theoretical framing enables future researchers to diagnose indicator gaps systematically and design remediation strategies accordingly.

These findings also have broader implications for debates on sustainable tourism governance and destination resilience. The dominance of institutional and technically oriented assessment approaches suggests that sustainability measurement in Mediterranean destinations is still shaped primarily by administrative and managerial priorities rather than by broader participatory governance logics. At the same time, the uneven treatment of sustainability dimensions and the limited inclusion of civil society actors raise questions about the resilience of current assessment models, particularly their capacity to capture social vulnerability, adaptive capacity, and locally grounded responses to tourism pressure. From a participatory destination management perspective, these patterns indicate that indicator systems may remain operationally useful but institutionally narrow unless they are supported by more inclusive and context-sensitive forms of stakeholder engagement.

5. Limitations

This review acknowledges several inherent limitations. The restriction to Scopus-indexed, English-language publications may have excluded relevant research published in regional journals, institutional reports, or grey literature—potentially exacerbating the identified geographic bias toward European contexts. The temporal scope of 2000–2024, while comprehensive, may have missed foundational work published earlier. The systematic review methodology relies on the quality and consistency of original study reporting, and variations in methodological detail may have affected the precision of categorical classifications. The single-database approach, while methodologically justified for consistency and replicability, may limit absolute comprehensiveness compared to multi-database searches. Future research must prioritise geographic expansion to underrepresented North African and Eastern Mediterranean destinations, developing culturally sensitive frameworks and cross-regional comparative studies that reflect the full diversity of the Mediterranean basin. The restriction to English-language publications, whilst necessary for coding consistency, may have introduced a language bias that contributes to the underrepresentation of certain countries—most notably France—where relevant scholarship may be published predominantly in other languages. Methodological innovation should focus on the integration of big data analytics, IoT sensors, and artificial intelligence for real-time monitoring and adaptive destination management. Participatory approaches deserve greater emphasis, positioning local communities as equal partners in indicator co-production rather than mere data sources, and integrating traditional and local knowledge alongside scientific monitoring. Finally, greater alignment with ESG-like reporting standards and the SDGs—through shared indicator definitions, transparent aggregation methods, and harmonised benchmarks—would strengthen cross-destination comparability, policy uptake, and the integration of destination sustainability performance into broader sustainable development governance.

A further limitation concerns the status of the Mediterranean Sustainability Assessment Framework (MSAF) proposed in this study. Although the framework is grounded in the systematic synthesis of the reviewed literature, it remains conceptually derived and has not yet been empirically validated through application to specific tourism destinations. Its analytical usefulness at the destination level should therefore be interpreted with caution. Future research should test the framework in concrete Mediterranean case studies in order to assess its operational applicability, contextual adaptability, and capacity to support destination-level sustainability assessment in practice.

6. Conclusions

This systematic review shows that research on sustainability indicators in Mediterranean tourism destinations has become methodologically well developed and increasingly policy-responsive, particularly through the use of quantitative assessment tools and the recent expansion of the field. However, its wider contribution remains constrained by three persistent imbalances: a strong geographic concentration in a small number of European Mediterranean countries, a systematic privileging of economic and environmental dimensions over social, governance, and cultural ones, and a stakeholder profile dominated by public and market actors with limited civil society participation. These findings show that sustainability indicator research in Mediterranean tourism destinations remains uneven in its spatial coverage, dimensional balance, and stakeholder inclusiveness. Addressing these limitations is essential if indicator-based assessment is to support more integrated and regionally applicable sustainability transitions across the Mediterranean.

The proposed Mediterranean Sustainability Assessment Framework (MSAF) has both theoretical and practical implications. Theoretically, it provides a structured lens for evaluating sustainability assessment systems in Mediterranean tourism destinations across three key axes: dimensional completeness, methodological pluralism, and contextual embeddedness. In practical terms, the MSAF can be used as a diagnostic and revision-oriented framework for reviewing existing destination-level sustainability indicator systems. It enables researchers, destination managers, and policymakers to assess whether an indicator set covers the full range of sustainability dimensions, whether it relies on a sufficiently plural methodological design, and whether it reflects the specific environmental, social, cultural, and governance conditions of the destination under examination.

The MSAF is not intended merely to restate the deficits identified in the literature review. Whereas the review diagnoses recurrent weaknesses across the Mediterranean research corpus as a whole, the MSAF translates these findings into a transferable appraisal structure for examining a specific destination-level sustainability assessment system. Operationally, it can be used to determine whether an existing indicator framework omits relevant sustainability dimensions, relies too narrowly on a single methodological logic, or insufficiently reflects the environmental, social, cultural, and governance conditions of the destination under assessment. In this sense, the MSAF supports not only diagnosis but also structured revision, by indicating whether the main need is to expand indicator coverage, diversify assessment methods, or strengthen contextual adaptation and stakeholder relevance. Accordingly, the operational novelty of the MSAF lies in its use as an assessment tool for reviewing and improving destination-level indicator systems, rather than as a further descriptive summary of problems already identified in the literature. Accordingly, the MSAF moves beyond corpus-level diagnosis by providing a practical structure for appraising, comparing, and revising destination-level sustainability indicator systems.

Using the MSAF, researchers and practitioners can:

(i)

identify missing sustainability dimensions;

(ii)

detect excessive methodological concentration;

(iii)

assess whether the framework is adequately adapted to destination context;

(iv)

prioritise revisions to the indicator system before it is used for monitoring or policy support.

This use is consistent with the review’s own findings that current assessment practice remains uneven in dimensional coverage, method choice, and regional representation.