Real Estate Trends and 15-Min Cities: A Scoping Review and Spatial–Economic Framework

Abstract

The 15-min city (15 MC) is an urban planning concept that organizes cities through proximity-based systems, enabling residents to access essential services within a 15-min walk or cycle. Although the health and environmental benefits of this model are well documented, its effects on the real estate market have received limited attention. This paper examines the impact of 15-min proximity-based urban planning models on land use patterns, property values, and sociospatial interactions in urban settings. It adopts a scoping review approach (structured mapping and synthesis of the available literature) and, using a transparent source selection process (PRISMA-ScR), compiles evidence on how functional accessibility, mixed uses, and proximity to green/public spaces affect prices and rents in residential and/or commercial real estate. The synthesis shows that proximity is often capitalized as a proximity premium, but it can exacerbate inequalities and displacement risks without accompanying regulatory mechanisms. Based on the findings, an operational spatial–economic framework is proposed that links (a) planning interventions, (b) functional accessibility, (c) behavioral adaptation, (d) market valuation reactions, and (e) governance/redistribution tools (e.g., land value capture, inclusionary zoning), as a diagnostic tool for assessing surplus value and displacement risk and as a basis for future GIS/hedonic testing.

1. Introduction

Modern cities are manifestations of the increasing conflict between their functional development and the need for sound urban planning. This manifests physically, mutating as required. In a society where everything is urbanized at an ever-increasing rate, and all environmental problems and societal pressures come together increasingly frequently, from environmental degradation to mobility imbalances to the affordability of urban real estate, building sustainable and resilient cities is now at once an ongoing goal but also something that needs doing at the same time for today’s societies. To improve social cohesion, sustainability, and resilience, new models of urban planning are sought to address modern challenges. Because residents can walk or cycle to essential services and recreational areas within 15 min, 15-min cities are cited as a prominent model for spatial accessibility [1,2,3,4,5,6,7]. Drawing on localism, proximity-based access, and neighborhood self-sufficiency, this planning strategy aims to address these issues [8].

The idea, albeit in other forms, has been mentioned previously and was first formulated by Carlos Moreno in 2016 [5]. Its basic principle is to restructure urban areas so that residents can meet most of their daily needs within a 15-min walk or bike ride from home. By implementing a new urban planning system that promotes social equity and sustainable development through regulated spatial and temporal management systems, the goal is to create sustainable urban environments. Many cities around the world are using the 15 MC model as a critical element in their recovery from the coronavirus pandemic and in their planning for new climate change resilience [2]. However, because this model directly affects the dynamics and structure of urban real estate markets, its impact extends beyond infrastructure and mobility to other urban parameters [9].

This paper addresses that gap by synthesizing peer-reviewed studies at the intersection of accessibility planning, urban economics, and property valuation, and translating the synthesis into an operational framework for planning appraisal and policy design.

More than a planning tool, this paper also suggests that the 15 MC model can serve as a strategy for the real estate market. The addition of new spatial parameters to the 15 MC term affects the distribution and valuation of urban land. Thus, a new spatial economic system is created by transforming urban planning into easily accessible micro-spaces that enable residents to exploit proximity. Research shows that real estate values increase significantly in areas with improved pedestrian access, green spaces, and mixed land-use patterns [10,11,12,13,14,15]. There are two connections between the real estate market and the 15 MC theory. The commodification of improved accessibility often further entrenches existing urban disparities. High-accessibility locations frequently attract capital investments, which raises real estate values and results in socioeconomic displacement [13,16]. By trying to bring society together while causing spatial exclusion, the policy creates an essential contradiction [17,18,19,20,21]. The implementation of spatial proximity policies in cities and their capacity to stop social segregation through land value mechanisms are the main issues that arise. To solve these problems, a comprehensive system must integrate economic geography, spatial analysis, and urban planning data.

Although the impact of walkability and green infrastructure on property values has been studied [13,15,22], their relationship to the 15 MC model remains poorly explored. Furthermore, the current research fails to establish a single theoretical framework that links accessibility elements to evaluation methods and planning processes for a comprehensive assessment.

This study seeks to fill this gap in understanding by conducting an extensive review of prior studies that analyze urban real estate market responses to proximity-based planning approaches. The study explores the impact of walkability, green spaces, mixed land use, and density on property values, demonstrating how proximity is reshaping the urban real estate market. Urban planners, policymakers, and researchers can leverage research data to develop appropriate spaces that advance social justice amid rapid urban change.

The paper makes four contributions: (1) it consolidates evidence on proximity-related price effects across residential and commercial markets; (2) it articulates a causal pathway (“cascading value chain”) from planning interventions to accessibility gains, behavioral change, and valuation response; (3) it proposes a five-layer spatial–economic framework that aligns measurable indicators and analytic methods with policy levers; and (4) it highlights governance conditions under which 15 MC transitions can enhance equity rather than reinforce socio-spatial sorting.

Related to existing frameworks that mainly approach 15 MC as an access coverage and accessibility indicators issue, this paper introduces three explicit dimensions that are often missing: (a) the timing of market response, i.e., that prices/rents can already be affected by the announcement/early implementation phase of interventions, (b) a valuation layer that incorporates valuation as a mechanism for capitalizing on proximity (proximity premium), and (c) a governance layer that links surplus value to regulatory and redistribution tools (e.g., value capture, inclusionary zoning) in order to limit the risk of displacement. Thus, the framework functions as a diagnostic tool that links accessibility, the real estate market, and policy.

2. Materials and Methods

2.1. Strategy for Searching and Selecting Sources

This research was conceived as a scoping review, i.e., a structured approach to mapping and synthesizing the literature that seeks to clarify concepts and highlight knowledge gaps, without requiring a homogeneous set of studies or primary empirical assessments [1,23]. The search was organized around three thematic axes corresponding to the key elements of the 15-min city and real estate valuation mechanisms: (a) functional accessibility/walkability, (b) green/public spaces and “green premium,” and (c) mixed uses/city morphology and “diversity premium.” For the evidence set, searches were conducted in the Scopus and Web of Science databases using combinations of terms covering 15-min city/proximity neighborhoods and real-estate outcomes/valuation (prices, rents, premiums, hedonic valuation), with a time range from 2000 to the present and a restriction to peer-reviewed articles/reviews (mainly English-language, yet the logic of the proposed framework is transferable and can be applied to other linguistic/institutional realities, provided that comparable data and indicators are available). In addition, targeted checks were used for the theoretical/conceptual framework (context/background), without being included in the PRISMA counts, which relate exclusively to the evidence set that feeds into the synthesis of findings.

The identification–selection–inclusion process is illustrated in the PRISMA 2020 flow diagram (Figure 1). In total, the search in Scopus and Web of Science yielded 250 records. After removing duplicates, 198 unique records remained were screened for titles/abstracts. At this stage, 93 were excluded. Subsequently, 105 full texts were evaluated for eligibility, and 51 sources were ultimately included as “sources of evidence” for the scoping synthesis and the formulation of the proposed spatial–economic framework. Full-text exclusions (54) mainly concerned studies without an explicit valuation outcome, without a proximity mechanism at the neighborhood/urban fabric scale, and/or with an inadequate methodological description.

This approach is applicable to the field of the 15 MC and to real estate markets, where different accessibility indicators, valuation methods, and variations in institutional/spatial context coexist. This methodology is developed in three major phases:

• A comprehensive literature search and screening process was performed in line with scoping review guidance, aiming to map the breadth of evidence, identify conceptual gaps, and support framework development, without conducting a primary empirical assessment or a brief summary of the magnitude of the result.
• Based on this evaluation, a critical analysis was generated by referencing some examples of how various international cities (Paris, Barcelona, Melbourne, Stockholm) employed the principles of Social Cohesion and the 15 MC model. In this study, the cities cited as examples are utilized not as primary empirical case studies with new data or field research. Instead, they are included as illustrative case evidence in the scoping synthesis, with the aim of linking the mechanisms emerging from literature (e.g., proximity premium, market reaction time, displacement risks) with recognizable policies and interventions in specific cities. Therefore, references to cities serve exclusively as interpretative/exemplary “policy anchors” to illustrate the mechanisms arising from the synthesis of evidence, rather than as a source of primary data or a basis for new empirical assessment in this article.

This procedure aligns with the rationale of scoping reviews, in which the mapping/coding process can be iterative and refined as evidence categories are clarified [24,25]. The review, based on prior research and secondary sources, aimed to characterize recurrent patterns in data, which include:

• the mechanism of formation of the phenomenon of “proximity premium”,
• socio-economic factors and how these shape the reinforcement of population displacement phenomena,
• the institutional structures and governance policies.

3.

Planning, accessibility, behavior, valuation, and governance are the key elements that constitute a five-part spatial economic framework. As this framework is interdependent, the feedback loop of spatial interventions plays a reciprocal role, contributing to social issues and real estate market dynamics.

The proposed methodology would address these fundamental tensions in real estate values across 15 MCs, particularly between economic capitalization and social justice, indicating that assessment must be a multi-parametric, multi-temporal process. This is done by analyzing three thematic areas:

• Addressing the Asymmetry: Other measures, such as the walkability index or access to green spaces, are valid metrics but do not provide a holistic view of the situation. But today’s systems for assessing health do little to determine large-scale qualitative categories of individuals’ perceptions of safety, emotional connections to places, or social trust in space. The model recommends using poetic and storytelling approaches (e.g., community mapping through interviews) to measure these dimensions.
• Time Level: Evaluating what the immediate financial effects are on property values and the longer-term social and environmental consequences, community resilience, and social marginalization. The framework enables this multi-temporal reading.
• Power and Equity Factor: The question of who ultimately gets to benefit from improved accessibility, as seen by the framework proposed here, is one that this methodological framework addresses. It seeks to analyze the distribution patterns of distance benefits across different socio-economic groups and to formulate methods to achieve an equitable distribution [26].

To assure comparability between heterogeneous studies, the selected articles were coded according to (a) the type of urban intervention (e.g., green infrastructure, pedestrianization), (b) the proximity indicators used (e.g., walkability indices, accessibility to green spaces), (c) the type of valuation and market (e.g., transaction prices), (d) the methodological approach (hedonic models, spatial econometrics), and (e) the social impact (e.g., gentrification, socio-spatial sorting). This coding fed into both the synthesis of the key trends and the structure of the proposed framework. Indicatively, the key characteristics of the reference cities (types of proximity interventions, common indicators, typical market effects, and associated risks) are summarized in

Table 1. Comparative recording of illustrative case evidence and linking to indices.

City	Proximity Interventions	Typical Indicators	Market Effect	Danger
Paris (15-min city proximity policies)	Pedestrianizations/active mobility infrastructure	Access to services, quality of public space	Upgrading the attractiveness of highly accessible areas	Gentrification/price pressures
Barcelona (Superblocks)	Reduction in the use of private car/“green islands”/improved walkability	Changes in accessibility/public space, environmental quality	Proximity premium/speculation	Displacement/touristification
Melbourne (20-min neighbourhood)	Local services/active mobility pilots	Service coverage, safety/comfort, car dependence	Mild/heterogeneous effects	Uneven spatial benefits
Sweden urban areas (longitudinal 15-min city logic)	Density/mixed uses/accessibility	Temporal accessibility indicators	Rise in values/income restructuring	Socio-spatial sorting

.

2.2. Equity and Governance Dimensions

Beyond selecting sources, thematic coding was used to ensure the synthesis was consistent and reproducible. In particular, data concerning (a) equity mechanisms and (b) governance/institutional issues affecting the implementation of the 15-min city were systematically recorded. The corresponding categories are summarized below and are used in the discussion of the findings.

The Imperative for Integrated Equity Mechanisms

The implementation of 15 MC strategies faces an essential deficiency as they do not include active equity-based solutions that work together as a system [2,18]. The planning process focuses on physical and environmental indicators (service radii and green cover) but ignores social protection measures [2,9,27]. The “Just 15-Min City” framework requires researchers to develop an equitable planning system that implements equity principles throughout the entire development process [19,28]. This includes:

• affordability assessments, which occur before and after infrastructure development [17,18]
• free rental zones situated near public transit stations [18,19]
• frameworks for distributing ecological benefits, where residents participate in planning and reap tangible benefits [9,28]
• mobility equity indicators to evaluate how transportation improvements affect access distribution patterns [2,29,30].

However, these elements support the documented requirement for a fair 15 MC model (“Just 15 MC model”), defined for both policy and finance, and the associated policies that address displacement challenges, social inequalities, and non-participation challenges.

Furthermore, “15-min” accessibility should not be interpreted solely as a geometric/temporal indicator [31]. Instead, it should be understood as the actual ability to move around for groups with different needs [32]. For people with disabilities, older adults, or parents with young children, the quality of the sidewalk, slopes, crossings, shade, rest areas, lighting, and sense of safety have a decisive impact on the “real” 15 min [33,34,35]. Therefore, proximity indicators and proximity policies must incorporate universal design and safety-by-design principles so that improving proximity does not lead to exclusion in everyday mobility.

Governance and Implementation Challenges

To implement the 15 MC concept successfully, organizations need to establish robust governance mechanisms, effective institutional coordination, and complementary policies. It seems easy because it is oriented toward proximity to the location. Yet its effective implementation requires painstaking policy coordination, long-term land management, and ongoing community participation [36,37]. Many urban areas continue to face implementation barriers stemming from fragmented governance, siloed planning, and market pressures.

Fragmented Urban Governance

The major problem is that the different levels and sectors each have their own institutions. In the case of standardized structures within urban municipalities, different sectors for healthcare, education, and residential areas are established; thus, the 15 MC needs a single territorial framework to link these services to transportation networks [4,19,38,39].

The European Commission’s Valencia CityLab Report highlights this issue, noting that Valencia used mobility hubs and green corridors to enhance local accessibility. The implemented solutions failed to address housing and educational inequality as different sectors worked independently without proper coordination [38,40]. The lack of joint responsibility in proximity investments leads to inconsistent results worldwide, which become evident [2,17,19,38].

Market Forces and Urban Form

Speculative, market-driven urban development makes governance more challenging to implement because it prioritizes short-term financial gains over fair space distribution [28,41]. Instead of funding public goods projects, developers in Paris, Toronto, and Sydney used increases in land value driven by density-enhancing mixed-use development and the expansion of green infrastructure to make money [2,42]. The 15 MCs’ accessibility benefits need protection from capital appropriation through government implementation of land value capture, inclusionary zoning, and social leasing mechanisms [21,43].

The implementation of superblocks, car-free zones, and tactical projects becomes fragmented when ad hoc pilots lack connection to metropolitan spatial strategies, leading to the neglect of peripheral areas [19,38].

Land Tenure and Institutional Power

The public sector presents a major governance issue, as land ownership shapes its operations and determines development outcomes. Public land assets in cities should apply the 15 MC principles to strategic planning for their public housing, school facilities, transportation systems, and other assets [38]. Few, if any, of those areas receive any meaningful return on investment, with private property owners able to use those property facilities for proximity improvements as their first foray into nearby rental income, due to limited public areas and poor regulatory control in the neighborhood.

For instance, the data show that public budget investments in green corridors led to value growth in San José, mainly benefiting private developers [44]. The state’s investments through the program served as capital-accumulation subsidies because they lacked mechanisms for value sharing and CBAs.

A similar issue is facing idle public assets, including empty schools and libraries and unused administrative land parcels that are prospective proximity nodes [5,17,28]. Although cities such as Barcelona and Amsterdam have begun to experiment with participatory reuse models, scaling such initiatives will require institutional agility, community trust, and legal frameworks for land transformation [17,19,42,45].

Metropolitan and Regional Coordination

When urban areas with functional regions extend beyond municipal boundaries, metropolitan governance becomes necessary [38]. The implementation of school zoning and urban forest programs in Greater Paris has been uneven due to the city and the Île-de-France region’s lack of cooperation [5]. Implementing more robust regional planning bodies, mobility agreements, and fiscal equalization mechanisms will enable the distribution of proximity advantages among various territories [2,38,43]. The successful models of integrated accessibility targets in Copenhagen and the city-region collaboration office in Seoul, which link housing, employment, and transport, serve as examples [2,42].

Governance Innovation

The solution to these institutional barriers requires scholars and policymakers to support governance innovation in line with current trends.

• Territorial governance models: The planning system should use territorial governance models that base their organization on actual geographic areas (15 MC zones) instead of administrative limits.
• Inter-agency task forces: The integration of transport and housing functions with climate and social planning happens through inter-agency task forces, which handle shared responsibilities.
• The community can participate in budgeting decisions through participatory budgeting and co-creation platforms, which enable them to shape 15 MC priorities and resource allocation.
• Digital governance tools: Using mobility and land use data to monitor proximity outcomes and spatial inequalities in real time.

The 15 MC requires extensive governance because its goal of equal access depends on how well government departments coordinate their work on land use, mobility, housing, and environmental protection. The 15 MC face a high risk of exacerbating spatial inequality because they lack proper governance systems to ensure equal resource sharing and community involvement.

3. Findings (Literature Synthesis)

3.1. Key Trends Identified

In accordance with the scoping review’s logical approach, before presenting the thematic findings in detail, it is valuable to summarize the main trends emerging from the field mapping [1,23]. Six recurring trends that connect proximity interventions to real estate markets emerge from the literature review.

First, improvements in functional accessibility and walkability are often capitalized into prices/rents through proximity or walkability premiums. Second, the strongest effects occur when interventions combine walkability, mixed uses, and high-quality public spaces. Third, in several cases, the market reacts as early as the announcement or preliminary implementation phase, creating discounting and speculative pressures. Fourth, proximity to green and public spaces creates a “green premium”, which can lead to green gentrification in the absence of protective policies. Fifth, land-use diversity is associated with a “diversity premium” under conditions of compatible use. Sixth, unless there are regulatory and redistribution mechanisms, premiums tend to intensify socio-spatial stratification and the risk of displacement.

3.2. Proximity and Real Estate Values

Walking is one of the most essential elements of the 15 MC model. Therefore, it emerges as a crucial element in this proposal for urban planning and the organization of the real estate market [13,15,46]. This approach seeks to promote accessible, healthy, and sustainable urban environments while reducing reliance on cars [5,29,47,48]. In any case, interventions that improve the likelihood of walking not only enhance quality of life but also ultimately alter economic dynamics and values as variables in urban geography.

According to urban economic theory, real estate values are directly influenced by proximity. From Alonso’s “rent-offered theory” [49] to Muth’s monocentric city model [50], to more recent polycentric models, land prices are affected by their proximity to the city center and the amenities available [51]. To do this, walkability evidence indicates that the spatial form in which cities are located has a positive, direct effect on property values, which further contributes to functional density in urban space and experience quality [12,52,53]. The economic rationale is obvious: demand for walkable spaces grows as access to job opportunities, services that matter, and places to socialize increases. The “walkability premium” may be due to property values that tap into this demand [13,22,47,54,55].

Research has shown that walkable areas have also raised property values [47,52,54,56]. Pivo & Fisher [13] conducted a pioneering study of commercial real estate in US cities, finding that walkable neighborhoods generated higher net operating income, higher occupancy rates of available housing, and higher capitalization rates and returns on property values. There have been similar results in housing markets, findings consonant with research [13].

Kim & Kim’s study [54], which used spatial regression models to analyze spatial data in Seoul, documented that some affordable neighborhoods experience increases in property values when factors related to walkability are accounted for and improved. In contrast, improving walkability appears to have little impact on housing costs in places where they are already high [54]. The reason for this discrepancy seems to be that walkability is a critical advantage for daily access to services in less expensive areas, which ultimately increases demand and increases prices [54]. In contrast, in costly neighborhoods, other factors, such as the quality of school infrastructure or social capital, tend to determine property values more [54]. In their research, Ivey & Bereitschaft [22] used a multiple linear regression model based on the hedonic pricing theory and found a statistically significant, positive correlation between walkability and property sale prices in Douglas County, Nebraska [22].

Ellder [18] conducted extensive research on Sweden’s urban development over a 25-year period. His findings documented that implementing integrated 15 MCs with varying characteristics leads to higher average household incomes and attracts more affluent social groups, highlighting the risks of urbanization and the increased cost of living [18]. In contrast, in urban areas with high housing prices, walkability did not affect prices [18]. Therefore, while improving accessibility and walkability is desirable, implementing the model may exacerbate social inequalities in the real estate market. This phenomenon is even more dynamic in densely populated areas [18].

In another European city, Graells-Garrido et al. [57] examined how superblocks modified Barcelona’s real estate market by affecting transport systems and property value appreciation. In this case, the creation of pedestrian-friendly zones significantly enhanced the attractiveness of residential neighborhoods. Conversely, it led to social tensions, especially in the early stages of the plan’s implementation, due to increased speculation in the real estate sector [57]. In a similar work, Ferrer-Ortiz et al. [11] examined how the principles of the 15 MC model were applied in Barcelona. The results documented that most residents of Barcelona currently live in areas with very high levels of protection in terms of coverage of basic urban services [11].

Global South experiences varying effects on walkability, influenced by how governments manage their areas, the presence of informal settlements, and the condition of their infrastructure [13]. According to a recent study [58], pedestrian accessibility and the traditional concept of pedestrian mobility are not interchangeable concepts. On the contrary, pedestrian accessibility is linked to proximity to road networks and corresponding infrastructure. In this case, properties near well-connected roads and sidewalks show a 15–25% increase in value [58].

The evaluation of the walkability premium relies on various measurement approaches, including Geographic Information System (GIS)-based indicators and hedonic price estimation models [11,59,60,61,62]. Beyond economic benefits, accessibility-oriented planning should prioritize pedestrian accessibility [2]. Gentle planning interventions prevent and avoid the phenomena of population displacement that are possible in the early stages of urbanizing neighborhoods, where design changes induce intense speculation on properties [2]. Walkability has been upgraded in the 15 MC model from a secondary feature to a fundamental structural element that determines the creation and distribution of urban real estate value [2,22,61].

3.3. Green Spaces and Proximity

Green infrastructure in the urban fabric is traditionally considered the basis of sustainable urban planning [29,63,64]. Accessible green spaces that meet high-quality and sustainability standards are conducive to the zone planned by 15 MC, helping address public health and social well-being issues and raising interest in urban capital [9,15,19]. The scientific literature has also reported the “green space premium,” the observation that being close to parks, forests, and other green spaces is associated with higher house prices [14,15,65]. Hedonic models, spatial econometrics, and indicators that capture both the accessibility of and the quality of the natural environment are among the tools used to document this relationship [14,20]. The association between green space and higher property prices is well established by the urban amenity theory, which posits that households tend to be amenable to environmental features that improve their quality of life and daily lives [10,60,66]. The value of green spaces can be capitalized in the property market, even though they are, a priori, public goods. This leads to greater demand, rents, and investment returns for such areas [20,66,67]. The 15 MC model considers green infrastructure, which has been essential throughout urban life by providing green places that foster urban vitality and value, so that access to green space should be the fundamental urban planning question [9,48].

Several studies conducted across diverse geographical contexts have reported on a relationship between property values and the proximity to green spaces. Urban green spaces are said to be significant for the appreciation of surrounding properties and for attracting residents and investors [66]. This study illustrates the impact of green space density on property values in the city of Ramadi, Iraq [66].

For each increase in the distance-to-green-spaces index, the “green premium” for a property was approximately 5% [66]. In contrast, this study acknowledges that negative externalities, such as industrial pollution, can also affect property values [66]. As Piaggio points out, the market value of a property is correlated negatively with its proximity to undeveloped natural areas (e.g., wetlands or riverbanks) [20]. In contrast, values tend to rise when property is adjacent to community and metropolitan parks [20]. Such spaces function as community assets by providing people with the right to socialize and to aesthetic improvement, as well as amenities and recreational activities. This, in turn, leads to increased demand and value in the local housing market [20].

Wu et al. [14] investigate the relationship between proximity to parks and housing prices in the city of Shenzhen, China. Their findings illustrate the strong positive influence of green space on residential house prices [14]. On a larger scale, they note that coastal parks are crucial because they blend recreational landscapes and natural environments, thereby enhancing urban appeal. They suggest that coastal parks have the most positive impact [14]. Therefore, in a similar study conducted in Shanghai, Ben et al. applied a hedonic-based model alongside spatial econometric models to eliminate endogeneity issues [10]. Greater access to green spaces also leads to higher housing prices [10]. In Europe, Trojanek et al. analyzed the effect of living near green spaces on property values of apartment stock in the Polish city using hedonic regression [68]. Houses located less than 100 m from green spaces have a value increase of 2.8–3.1%, as found in the current analysis [50]. This effect is statistically insignificant when properties are more than 400 m from green spaces [68].

In a broader context, a systematic literature review by Chen et al. [59] confirmed that urban green spaces are positively associated with property values. In this way, residents’ quality of life is improved [59]. However, the extent of this phenomenon varies significantly across studies, depending on the study’s time frame, the geographical and cultural characteristics of each city, and the type of property and residents’ socioeconomic status [59].

Despite their benefits, investments in green infrastructure can sometimes lead to social issues related to the greening of the urban environment. Green spaces, when implemented in low-income neighborhoods, attract higher-income residents, who ultimately displace existing residents by increasing housing prices [21]. In the 15 MC concept, this risk is increased, as the specific model emphasizes the development of local services [18,21]. Avoiding these phenomena can be achieved through the establishment of protective measures, the implementation of rent control systems, the introduction of more comprehensive social housing programs, and a strict system for recording property values and their changes [69].

3.4. Mixed-Use and Urban Morphology

The principles of the 15-min city model are the development of compact, multifunctional communities where employment, education, healthcare, businesses, and recreation co-exist in proximity [2,5]. The resulting diversity of land-use systems is transformed into a strategic planning tool through this spatial approach, which aims to improve daily quality of life, reduce travel, and increase local economic activity [2,4,5,43,70]. Yet, the principles of the real estate market are not followed when services and urban functions are over-concentrated in specific areas and zones. Locations with multiple functions attract significant interest from buyers, thereby increasing property prices [18,19,38]. Thus, the model improves urban sustainability but creates social imbalances that require additional policies to maintain affordable housing and prevent the relocation of higher-income residents [28,43].

Empirical data confirm that areas with a substantial diversity of land uses axiomatically attract increased investment and lead to higher property values. Integrating commercial and residential functions in these areas increases economic activity and market independence and improves financial stability [12,41,71]. Business and infrastructure productivity, and social interaction that precede or follow the concentration of urban activities, create a cycle of values that supports increased urban growth [72].

A study in Hong Kong by Liusman et al. [53] revealed a clear correlation between mixed land uses and higher office rents [53]. In particular, rents decreased as the distance from commercial and tourist services increased, while tenants preferred to pay more for mixed-use buildings than for single-use ones [53]. The central thesis of this study is that mixed-use areas facilitate agglomeration economies, ultimately enabling optimal interaction among urban activities and reducing transaction costs through improved accessibility between customers and partners, leading to higher property purchase and rental prices [53].

Elldér, in his own research in Sweden, demonstrated that multifunctional policies lead to long-term stability in property values, especially in second-tier cities that had faced development challenges due to monofunctional development planning [3]. Land use diversity acts as a buffer against economic fluctuations [3].

According to research by Song and Knaap [71] in Washington County, Oregon, combining certain land uses with residential properties increases their value [71]. Proximity to neighborhood-level commercial uses or their greater presence in the community also contributes to higher property prices [71]. Analysis shows that strategic mixed-use land-use planning, combined with residential areas and incorporating service businesses, leads to significant increases in property values [71].

Koster and Rouwendal [12] state that residents of Rotterdam perceive land-use diversity as a positive phenomenon that increases property values. A “diversity premium” is ultimately created when land uses related to administrative services, education, healthcare, and retail are shown to positively affect housing values [12]. Housing prices can increase by 1.1% to 3.4% in response to a typical increase in land use diversity, especially when compatible, low-disruption land uses are included [12].

Compact city forms can support mixed-use sustainability, whereas urban sprawl typically undermines it. However, urban density alone does not automatically lead to greater accessibility or higher property values [4,42,57,73,74]. The 15 MC model framework shows that mixed-use development, combined with compact urban planning and efficient transportation systems, creates accessible, sustainable communities that enhance social cohesion [2,5,28,41].

3.5. Planning Frameworks in the Global Scene

In practice, the 15 MC model generates different implementation effects, given that cities create their own institutions, spatial planning frameworks, and their own property markets with distinct characteristics [2,17,42]. Despite the model’s theoretical intent to provide universal access to services within walking distance, results differ across actual implementations [3,28]. Institutional capacity, market structure, and socio-cultural context are the three main factors determining the effects of implementation efforts. The section assesses the application of 15 MC principles in a global urban context and their impact on the real estate market, value creation, and spatial transformations in social dynamics.

As Paris adopted it in 2018 as a new strategy for urban planning and urban development, the 15 MC concept is based on that city [2]. Some interventions were undertaken in parallel with the “Ville du quart d’heure” as the main political narrative, such as pedestrianization, the conversion of schoolyards into green spaces, the extension of bike routes, and the encouragement of local “quartiers de proximité” [28,38]. Such initiatives aim to improve the walkability of public spaces and redistribute public space, reducing vehicle traffic [5,28]. While some of the positive gains include better environmental quality and service proximity, the policy is met with social issues of inequitable development and gentrification pressures, especially in central districts characterized by high real estate values, which have the potential to induce spatial and social segregation [2,18].

Indeed, Barcelona serves as an excellent case study of accessible and 15 MC-oriented urban transformation [11,57]. The main project that is converting traffic infrastructure into pedestrian-friendly zones, including green areas and basic community amenities, is the “superblocks” (superilles) scheme [38,63]. The actions taken in these areas aim to rehabilitate public spaces as green urban areas, increase biodiversity, and use urban transport systems for environmental purposes [5,53].

Meanwhile, studies such as those by Graells-Garrido et al. [57] are among many that pursue this line of research. Graells-Garrido et al. explore how 15-min accessibility enhances residents’ mobility, as a positively correlated factor in their model. Still, results in gentrification and social exclusion in urban places, reaping the benefits of the access [57]. The “20-Min Neighbourhood” strategy implemented by the city of Melbourne encourages the provision of safe cycling and shared transport options locally. Three neighborhood pilot projects that applied bottom-up approaches and co-planning principles demonstrate the method’s success. This allows the city to create pedestrian and bicycle infrastructure and green spaces, but it suffers from a high level of car dependency among its citizens [42].

Milan is used as a case study for the 15 MC in the work of Marchigiani & Bonfantini [38]. The 2021 election campaign of Mayor Giuseppe Sala introduced the “15-min city formula”, which aims to build a livable city by delivering work and services accessible within 15 min, improving health, safety, and urban resilience [38,75,76]. Milan’s 2012 Territorial Governance Plan (PGT) used «Nuclei of Local Identity» (NILs), which organize sections along different cultural and social status axes, thereby creating service demand [38,77].

Portland, Oregon, is a case in point for both integrated transportation systems and urban planning [78]. That includes state-level imperatives on urban growth limits, policy reversals away from highway expansion, and land use plans around existing and future light-rail stations. Research has also been done in Portland to examine walkable forms in urban areas [78].

As a central component, Bogota has adopted the 15 MC principle into its urban policy framework. Strategic action is being taken to promote healthy lifestyles, reach more at-risk strata, and increase micro-mobility [38,42,79]. The program achieves its purpose through three main pillars: supporting wellness by helping individuals change their lifestyles; providing services to at-risk communities; and facilitating local transportation. The “Barrios Vitales” initiative, implemented in April 2021 as an outreach program, aimed to encourage neighborhood beautification and regeneration initiatives by motivating residents [38,48].

Based on new research by Balletto et al., the city of Shanghai has adopted the “15-min Community Living Circle” model, with the basic components proposed by Tian et al. [80], as shown in recent survey findings. The city of Shanghai has created performance-based measurement systems to monitor Key Performance Indicators that assess the impact of its 15 MC model on residents’ quality of life [2].

In various cities around the world, the 15 MC model has been implemented and proven effective in improving daily living. Physical infrastructure and equality policies that guarantee access for all rather than giving it to a few privileged habitats are necessary for proximity’s success.

To support the qualitative findings,

Table 2. Indicative quantitative ranges of proximity-related premiums reported in the literature.

Mechanism	Indicative Range of Market Effect	Observation
Proximity to green space	~2.8–3.1% (at short distances)	The effect diminishes with distance
Distance from green space index	~5% (in specific studies/indices)	Depends on type or quality of green space
Connectivity/physical infrastructure	~15–25% (in some contexts)	Strong dependence on urban context
Land use diversity	~1.1–3.4%	Subject to compatibility

summarizes indicative quantitative ranges of effects (premiums) reported in the literature and used here as evidence base. Market effect mainly refers to: (a) residential transaction prices (€/m² or total price), (b) residential rents, and, where available, (c) commercial property indicators such as NOI/cap rates or rents.

4. Discussion

4.1. Spatial–Economic Impacts

As identified in the literature, the spatial configurations that emerge from the 15 MC model in contemporary societies function not only as planning principles but also as determinants of real estate values [2]. The successful integration of these elements into the urban form has reshaped the real estate market. Although the model’s original intention was to promote sustainable and equitable neighborhoods, its effects reveal an additional function: reshaping values through proximity [13]. In several cases, both the application of the principles of 15 MC and increased access to amenities and services were associated with price increases in both residential and commercial real estate [13].

This result is due to the so-called «proximity premium», the market’s response to improved accessibility and functionality of neighborhoods [81,82]. The “proximity premium” refers to the additional value (in price/rent) that the market attributes to properties due to their increased operational proximity to services/amenities, compared to otherwise similar properties [13,47]. Features such as time and cost savings, environmental benefits, and an improved quality of life, generated by the ability to meet basic daily needs on foot, are effectively capitalized on in land value [13,61]. The new patterns of desirability emerging from this development lead to increased investment in areas optimized for proximity [3].

The case of Barcelona offers a vivid example of the way an intervention that reduces car traffic and upgrades public space can translate into changes in neighborhood attractiveness and, ultimately, into a «proximity premium». Superblocks rearrange functional proximity, enhance walkability and public space use, and concentrate multiple qualities (e.g., comfort, safety) that the market tends to value. The literature on the implementation of superblocks points out that, in addition to the benefits, early speculative pressures may also arise, especially when interventions signal a broader upgrade of the area. This highlights precisely why proximity interventions need parallel regulatory and redistribution tools so that the premium does not become a mechanism of exclusion [57,83].

The implementation of the 15 MC, while seeking to improve accessibility and quality of life, carries the risk of spatial value disparity. The concentration of services and environmental benefits leads to the capitalization of the “premium of proximity,” transforming high-quality neighborhoods into “islands of privilege” [83]. This process acts as a catalyst for speculative real estate appreciation, which is discussed extensively in the literature on the relationship between urban planning and real estate capital. This sharp revaluation of values can lead to the displacement of vulnerable populations, as they are unable to afford the increased housing costs. Therefore, the success of 15 MC requires the immediate implementation of anti-gentrification mechanisms and the integration of equality-based solutions to ensure the fair distribution of benefits and avoid reinforcing existing social inequalities [83,84]. Figure 2 below depicts how uneven levels of proximity/accessibility within metropolitan areas may translate into localized real-estate value premiums (“bubbles”).

4.2. Accessibility as a Value Driver

Location is a key determinant of price via geographical distance as well as functional and empirical distance [13,82]. Research indicates that real estate added value is associated with its proximity to amenity clusters, encompassing green spaces, transportation, health and educational infrastructure, as well as commercial properties [2,82]. A similar trend has been observed in research spanning several years, conducted in various locations and economies, where areas with superior walking access and extensive amenities experience rapid, sustainable growth in property values. That is, these improvements are responsible for fundamental structural changes in urban demand [57,81].

4.3. Real Estate Markets’ Sensitivity

The real estate market achieves greater value and resilience through multi-use development in accessible locations, according to research across various urban settings [28,41,85]. The use of vertical and mixed-use planning also plays a catalytic role. This phenomenon is not limited to traditional urban centers but also extends to peripheral or previously undervalued areas, where interventions are accompanied by effective transportation links and adequate public infrastructure [82]. At the same time, the increased attractiveness created by improved proximity can lead to intense speculative pressures and gentrification [2]. Often, the mere announcement of a project or new infrastructure leads to a premature rise in land prices, even before the actual operational changes are implemented, making the way the planning is communicated a critical factor in shaping market trends [13].

4.4. Feedback Loops Between Planning and Capital

The property market and the planning of the 15 MC are in a reciprocal relationship. Demand is driven by urban planning decisions, with planning implementation influenced by market trends [81,82]. Investors and developers apply the logic of proximity to add value through mixed-use projects, green spaces, integrated educational or commercial activities, and low-traffic streets or sidewalks [2,63]. This feedback process opens the possibility of public–private collaborations that better align accessibility goals with business incentives [86]. However, it also poses the problem of equitable distribution, since the added value resulting from such investments may—without appropriate policies—be captured mainly by landowners and large developers [16].

4.5. Risks of Spatial Inequity and Displacement

The 15 MC is promising for contemporary urban development. Yet it also creates grave problems, as it can lead to geographic disparities and force residents to move from their existing dwellings. Improvements in accessibility, green infrastructure, and walkability increase property values beyond the financial means of the original occupants. Studies have shown that access barriers created by market-based proximity systems contradict the goals of social inclusion.

4.6. Planning for Proximity, Creating Scarcity

The same principles that improve neighborhood sustainability through pedestrianization and green space development also make the housing market more attractive [42,87,88]. This creates a sudden increase in housing costs and land-market inflation, leading to the displacement of low-income residents from their homes [51]. The “Superblocks” initiative in Barcelona led to a two-year rise in property values. It forced residents to abandon their homes in areas such as Sant Antoni, which were later restored to better condition [57]. Paris adopted pedestrian zones and new parks, introducing affordability problems in the central arrondissements that pushed working-class families to move to the suburbs. The theory of green gentrification has been widely researched, as environmental benefits in the neighborhood trigger market incentives that raise housing prices beyond residents’ affordability [21,89].

4.7. Socio-Spatial Sorting and Uneven Access

15 MC interventions offer distinct benefits at different paces, depending on the urban environments in which they operate [90,91]. Urban development is two-speed, with most investments going to profitable areas. This observation has been demonstrated by Pérez Molina & Vargas Aguilar [44] in San José, where middle-income regions showed increases in land values [92]. Conversely, a negative correlation was observed between walkability and housing prices in Shenzhen [61,93]. That is because of car dependency and the location of newer, more expensive properties [61]. Access to commerce amenities has a significant positive relationship with housing prices in Shanghai. However, when housing prices reach a specific value (approximately 61,200 yuan/sqm), this relationship becomes insignificant, highlighting that expensive homes are affected by other factors [80]. The detrimental impact of this trend primarily affects renters, the elderly, and minority communities, who must cope with higher rental costs as they seek alternative housing [2,16,78,94,95].

The institutional/intergovernmental conditions for implementation and the equity mechanisms used as coding axes are presented in Section 2.2 and are used here to interpret the findings.

5. Toward a Spatial–Economic Framework for the 15-Min City

As demonstrated in previous sections, the 15 MC represents more than spatial planning principles; it functions as an urban economic system that transforms how land values are distributed, how capital flows through cities, and how people move between places. Nevertheless, the current applications of 15 MC lack frameworks that combine its spatial reasoning with its economic effects. To fill this gap, this section proposes a spatial–economic framework that analyzes how planning interventions aligned with the principles of 15 MC generate changes in accessibility, user behavior, land valuation, and, ultimately, in socio-spatial dynamics.

The proposed framework is not just a repetition of trends; it transforms them into a functional evaluation logic. Specifically: (a) it converts the proximity/walkability/green/diversity premium into measurable variables (accessibility indicators, service coverage, proximity to green spaces, diversity of uses); (b) it combines these variables into analytical valuation tools (hedonic models, spatial econometrics, quasi-experimental designs where available), (c) it clearly introduces the question of “when” (timing/market discounting) and “who benefits” (distributional effects, displacement risk), and (d) it matches the potential excess value generated by proximity investments with regulatory/redistributive tools (value capture, inclusionary zoning, CBAs, targeted affordable housing). Thus, the framework serves as a diagnostic tool that enables the prediction of potential value increases and the timely activation of protection policies.

As 15 MC serves as a baseline for proximity rather than a rare privilege, competitive differentiation in values tends to shift from simple proximity to the quality of urban and architectural design. Once access to basic services is spatially balanced, prices are more influenced by place quality and urban planning characteristics, which have been shown to affect real estate values beyond simple spatial proximity [96]. At the same time, the functionality of buildings and the quality of infrastructure are becoming increasingly important, especially in hybrid working conditions, where the flexibility of spaces, energy efficiency, acoustic comfort, and the ability to adapt residences to multiple uses directly affect their utility and economic value. The use of green and “smart” infrastructure, and energy-efficient shells creates new value premiums that are not related to distance but to the long-term economic and environmental performance of the built environment [97].

The 15 MC requires three fundamental spatial components to establish its framework.

• Proximity to services and amenities, within a 15-min walk or cycle
• Diversity of land uses and urban functions within neighborhoods
• Density and compactness to support transit, social infrastructure, and public life.

These interventions transform urban systems to create accessibility advantages by reducing travel time, improving health outcomes, enhancing social interactions, and lowering transportation costs. The economic value of these non-monetary benefits becomes quantifiable in land markets because locations that are easily accessible generate economic value.

Urban interventions create a feedback loop between spatial planning and market behavior by improving accessibility and altering perceptions of distance, leading to behavioral changes, rising amenity values, and subsequent market price adjustments. The cascading value chain is presented in Figure 3.

The main objective of urban interventions based on strategic urban planning and mixed-use planning is to improve people’s access to essential services and amenities (Accessibility Gains) [2,9,12,29]. Reducing reliance on private automotive travel enhances the perception of proximity among urban inhabitants, and when their experiences align with expectations, they are more likely to use available services (Behavioral Shift) [41]. Since buyers consider proximity to amenities such as parks, schools, and stores, it is evident that walkability is regarded as an amenity premium [13,15,80]. Elldér found that high density, combined with mixed land use and a diverse range of services, is a prerequisite for increasing housing market value, as highlighted in her sample of 200 Swedish cities (Land Value Recalibration). The risk of social exclusion and gentrification is closely linked to the conversion of proximity advantages into elevated property prices [2,3,13,22].

And the proposed spatial–economic framework proceeds through five overlapping components:

• The Planning Layer (Spatial Intervention).
• The Accessibility layer (Functional Proximity).
• Behavioral layer (Mobility and Lifestyle changes).
• The Valuation layer (How the Real Estate Market reacts).
• Regulation and Redistribution is the governance layer.

Figure 4 summarizes the proposed five-level spatial-economic framework for the 15-minute city.

In terms of causality, planning interventions (e.g., pedestrianization, green infrastructure) function as independent variables (inputs). Changes in functional accessibility and use/mobility (the accessibility and behavior layers) act as mediators, translating interventions into everyday proximity benefits. The main outcomes are reflected in the valuation layer (prices/rents, price gradients, proximity premiums) and distributional effects (displacement risk, rent burden). The governance layer acts as a moderator, influencing who reaps surplus value and to what extent inequalities are reduced.

The innovation of the proposed spatial–economic framework is that it treats the 15 MC not exclusively as a technical goal of spatial accessibility, but as a mechanism for producing and redistributing urban economic value. Unlike approaches that are limited to measuring “service coverage” or isochrones, the present framework explicitly incorporates (a) the valuation layer, i.e., real estate market behavior (proximity premiums, expectations, price gradients) and (b) the governance layer, i.e., the regulatory/redistribution tools needed to ensure that proximity premiums do not become a mechanism of exclusion. In this way, the framework functions as a diagnostic tool, linking interventions, indicators, valuation methods, indicators, valuation methods, and policy tools into a single decision-making sequence.

Planning dimension includes specific changes in nature, such as broader sidewalks, green corridors, mixed-use zoning, and decentralized community buildings, among others. The physical interventions represent the real-world implementation of proximity-based planning, which serves as the foundation for the 15 MC model.

The accessibility aspect involves adjusting the time between habitats and urban services, accounting for both actual travel time and how people experience safety, comfort, and convenience. Because greater accessibility makes locations more appealing, urban zones gain economic value and become more competitive in the market.

The behavioral dimension shows how people change their behavior when they come across new close living arrangements. Local economies are activated through joint efforts to walk more, shop locally, use public spaces, and reduce automobile use.

A favorable impression of neighborhood appeal is created by increasing local activity and foot traffic, which significantly affects real estate market values by raising demand for local properties. A “vibrant” neighborhood, which characterized by active streets and everyday use of public space, reinforces the proximity benefits of the 15 MC and supports local economic performance. Developers and landowners modify their prices in response to anticipated shifts in the real estate market, creating what experts call the “proximity premium.” Accessibility improvements lead to these types of premiums and become evident soon after implementation, according to evidence from international studies and the literature.

The governance dimension is finally the most crucial factor because it determines who will obtain and distribute the value generated by proximity enhancements. Cities that use land value capture, inclusionary zoning, and community benefit agreements can redirect the value generated to support social infrastructure and affordable housing development. Private entities gain control over market-led city benefits when redistributive systems are absent, resulting in growing spatial inequality and urban population displacement.

The proposed framework operates in a circular rather than a linear fashion because market responses to proximity advantages create feedback mechanisms that can influence future policy and investment choices. Increased public spending is made possible by increased municipal revenue from rising property values. New regulatory strategies are necessary, though, because they also foster market speculation and resident displacement. Further, when city expansion/housing supply is constrained by regulations and reactions from incumbents, improvements that increase attractiveness/productivity tend to translate into higher housing costs and stronger capitalization in property values, reinforcing the scarcity mechanisms reflected in the framework [98].

Operationalizing this framework requires that each dimension be matched with appropriate policy instruments and institutional layers, as presented in

Table 3. Layer-Instrument connection of the framework.

Strategic Policy Instruments	Layer
Zoning reform, urban design guidelines, streetscape investments	Planning
Transit prioritization, pedestrianization, and active mobility subsides	Accessibility
Behavioral nudges, incentives for local commerce, and telework policies	Behavior
Property tax adjustments, rent regulation, and market monitoring	Valuation
Inclusionary zoning, rent regulation, and market monitoring	Governance

:

Through its fundamental organizational structure, the spatial–economic framework connects urban planning, urban economics, and urban governance. According to this viewpoint, the 15 MC is a quantifiable system that generates economic effects through its spatial interventions [99]. Because of the dual nature of the 15 MC project, which necessitates systems to distribute its value creation among stakeholders, the approach acknowledges that planning decisions have distribution effects. The operational mapping of the framework—with layers matched to indicative indicators, methodological choices, and policy leyers—is summarized in

Table 4. Layer-Instrument operationalization matrix (indicators, methods, policy levers).

Layer	Indicators & Typical Data	Analytical Approaches	Policy Instruments
Planning (spatial intervention)	Zoning and land-use rules; facility sitting; street/cycle-network upgrades; green corridors. Data: plans, zoning, network, POIs [100], project logs.	Policy coding; GIS network analysis; before-after mapping.	Complete streets; superblocks; mixed-use zoning; public facility sitting; green infrastructure programs.
Accessibility (functional proximity)	15-min accessibility score; cumulative opportunities; travel time to essential services; equity of coverage. Data: network, GTFS, service locations, population grid.	Isochrones; accessibility indices; spatial inequality metrics.	Service standards; targeted investments; transit and micro-mobility regulation.
Behavior (mobility & use)	Mode share; local trip rate; footfall; park visitation; perceived safety/comfort. Data: surveys, counts, mobile phone data, business registry.	Interrupted time series; panel models; activity-based/agent-based models; mixed methods.	Public space programming; safety measures; participatory design; support for local commerce.
Valuation (market response)	Price/rent gradients; price per m2; cap rates; development permits; early displacement signals. Data: transactions, rents/listings, permits, parcels.	Hedonic models; spatial econometrics; DiD; event studies; repeat-sales.	Vacancy/anti-speculation taxes; development controls; uplift-triggered affordability requirements.
Governance (redistribution)	Share of uplift captured; affordable unit delivery; rent burden; evictions/displacement; equity KPIs. Data: assessments, budgets, housing registry, eviction data.	Value capture accounting; distributional impact assessment; equity audits [101]; scenarios.	Land value capture; inclusionary zoning; social housing mandates; rent stabilization; community benefit agreements.

.

To further increase the applicability of the framework in a real-world setting, its operational use can follow a basic GIS workflow: (a) definition of categories of “essential services” (work/education/health/green spaces/retail), (b) calculation of 15-min isochrones (walking/cycling) at the neighborhood level, (c) production of accessibility indicators (cumulative opportunities, coverage equity), (d) linking the indicators to sales/rental data for hedonic or spatial econometric testing, and (e) identifying areas of potential surplus value and displacement risk so that policy tools (value capture, inclusionary zoning, targeted affordable housing) can be activated in a timely manner. This paper does not implement primary GIS mapping, but provides the structure and steps for subsequent empirical verification.

Empirical testing can be done via (a) hedonic/spatial econometric models where accessibility indicators are introduced as explanatory variables in prices/rents, and (b) quasi-experimental designs (e.g., event studies or difference-in-differences) around phases of proximity interventions, in order to estimate the timing of effects and identify early signs of displacement.

6. Conclusions, Limitations, and Future Research

This article has demonstrated that the 15 MC process may be more than a theoretical planning approach. The system acts as a value-generating spatial–economic framework and impacts property transactions, land management, and the social and spatial configuration of urban neighborhoods.

Furthermore, the implementation of the 15 MC in unequal spatial conditions can lead to local “islands” of real estate value (value bubbles), as accessibility is capitalized into prices as a premium. This phenomenon highlights the need for proximity planning to be accompanied by policies that ensure affordability and a balanced spatial distribution of benefits.

Premium is more than luxury living amenities; it embodies a wholesale transformation in urban values, creating a paradigm shift where the basis of class and economic status lies in quotidian accessibility.

This research goes beyond documenting trends to construct a theoretical framework that outlines the nexus between urban planning and the workings of these markets. We outline the spatial–economic framework that demonstrates when a physical factor, such as an urban planning contribution, such as the extension of sidewalks and the organization of amenities, or changes in zoning and construction, leads to functional accessibility in such an urbanism. Adding these together produces behavioral changes (people move within their area and use their neighborhoods), which in turn lead to changes in the market. The framework shows that planning means accessibility—demand, which in turn resets value structures.

This reordering of values is not always socially acceptable, though. The study shows that the 15 MC can more quickly lead to social segregation, displacement, and exclusion among various population groups due to inadequate governance systems. Studies show that gentrification, which raises housing costs and jeopardizes the stability of rental agreements for vulnerable populations, such as the elderly and marginalized communities, can result from proximity-based planning in high- and medium-demand areas. The 15 MC agenda of Mayor Hidalgo in Paris introduced environmental enhancements that improved living standards, yet these improvements exacerbated housing affordability problems in the city center.

The actual issue stems from unregulated value production arising from proximity principles rather than the principle of proximity itself. The rapid capitalization of accessibility improvements occurs in urban areas that have experienced high levels of financialization. 15 MC initiatives function as capital-upgrading tools rather than community-inclusion instruments because they lack mechanisms for value capture, rent regulation, and social housing integration.

The assessment aims to create an equity-based governance system for the 15 MC, rather than eliminating the current system. The research identifies five fundamental governance capabilities that are necessary for successful 15 MC implementation.

• Cross-sectoral planning integration requires the unification of work between mobility and housing departments, health and education sectors, and environmental protection agencies.
• Land value captures and redistribution, meaning recovering part of the value uplift generated by public interventions to fund affordable housing and infrastructure.
• Inclusionary zoning and social housing mandates, as the law demands that proximity-enriched developments under inclusionary zoning and social housing obligations remain accessible to people from different income levels.
• Spatial equity audits and participatory tools through measuring access inequalities and community participation in priority settings.
• Regional and metropolitan governance systems to prevent fragmented implementation and spatial inequalities between administrative areas.

Urban administrations often exhibit a political reluctance to regulate markets, as their policies can lead to market success, yet they continue to maintain separate institutional systems. The spatial–economic framework developed in this paper serves as a diagnostic and planning tool to help planners, economists, and policymakers trace the connections between planning interventions and their resulting socio-economic effects.

The proposed study provides a theoretical underpinning for the claim that the 15 MC serves as an active system that creates space, redistributes value through physical proximity, and functions as a political battlefield, economic resource, and social entitlement. With a focus on social justice, the real estate market, and urban planning, the framework provides a 360-degree view of proximity planning.

The paper also suggests that proximity analysis thus requires not merely considering distance-based measures, such as buffers and walkability scores; instead, it also highlights how spatial relationships to power structures, capital distribution, property ownership, and temporal factors influence closeness. Proximity for whom? At what cost? Under what governance regime? Achieving the 15 MC in future research and planning practice will be the challenge of answering these key questions.

The research findings highlighted that it should consider how physical planning interlocks with institutional development and social and spatial management systems to enable effective proximity control. The 15 MC serves as a dynamic terrain around which urban space and equity struggle, and people must make decisions about the future distribution of value, access, and equity, to be determined through engagement. If proximity is framed purely as a technical accomplishment or a lifestyle luxury, it will be commodified. The 15 MC should become a fundamental human right, at the very least, spurring transformative urban development and ensuring that all citizens have the same opportunities. Finally, this paper provides a timely critical examination of the 15 MC concept, which has been gaining traction worldwide.

Future work can extend the framework to commercial property and office markets under hybrid work, incorporate energy-performance and climate-risk indicators, and explore distributional effects by tenure (owners and renters), income group, and life-course stage.

For the real estate market to participate in 15 MC transitions without undermining social solidarity, specific institutional and planning conditions are required. Firstly, clear and measurable proximity targets to reduce uncertainty and limit speculative discounting. Secondly, systematic monitoring of early signs of surplus value and displacement risk, so that interventions are accompanied by timely safeguards. Thirdly, tools for capturing and redistributing surplus value so that part of the proximity premium is returned to affordable housing and social infrastructure. Fourthly, cross-sectoral coordination (transportation, housing, and land use) so that proximity investments are not fragmented. Lastly, participatory processes that incorporate the needs of vulnerable groups into intervention targeting. Under these conditions, the framework functions diagnostically, identifying where surplus value is likely to be generated and activating redistribution mechanisms in a timely manner so that the benefits of proximity are socially diffused.

Limitations include the heterogeneity of contexts and methods across the reviewed evidence and the absence of new primary empirical estimation within a single city setting. Future research should validate the framework with longitudinal transaction data, quasi-experimental designs (e.g., difference-in-differences around phased proximity interventions), and multi-city comparisons that explicitly model housing supply constraints and governance capacity.