World Urbanisation prospects report

 The Degree of Urbanization (DEGURBA) methodology is a core innovation and foundational component of the World Urbanization Prospects 2025 (WUP 2025), representing a significant shift toward providing internationally comparable urbanization data.

Methodology of the Degree of Urbanization (DEGURBA)

The DEGURBA is defined as a globally standardized method for classifying all areas of a country into mutually exclusive categories: cities, towns (or semi-dense areas), or rural areas.

Core Mechanics and Inputs

This harmonized methodology relies on new geospatial methods and a consistent application of criteria globally.

1. Criteria: DEGURBA uses a combination of population size, density, and contiguity thresholds.
2. Input Data: The method applies these thresholds to 1 km² population grids and uses satellite data derived from remote sensing technology. The crucial inputs come from the Global Human Settlement Layer (GHSL) project, which produces multi-temporal datasets including built-up area grids (GHS-BUILT) and population grids (GHS-POP).
3. Process Stages: The methodology involves a two-stage classification:
   • Stage 1 (Grid Level): Classifying 1 km² grid cells based on population density, contiguity, and population size thresholds.
   • Stage 2 (Spatial Units): Using the grid cell classification to categorize small spatial units (like municipalities) into mutually exclusive classes, based on where most of their population resides. The WUP 2025 analysis primarily relies on the grid level classification because a worldwide dataset of small spatial unit boundaries is not openly available.
4. Classification Levels (Level 1): DEGURBA distinguishes three main types of areas:
   • Cities (Densely Populated Areas): Areas with a high density (at least 1,500 inhabitants per km²) and a large population (at least 50,000 inhabitants).
   • Towns and Semi-Dense Areas (Intermediate Density Areas): Urban clusters outside of cities with a moderate density (at least 300 inhabitants per km²) and a population of at least 5,000 inhabitants. This category includes dense towns, semi-dense towns, and suburban/peri-urban areas.
   • Rural Areas (Thinly Populated Areas): Consist of grid cells with a density below 300 inhabitants/km², or denser cells not part of a city, town, or semi-dense area.
5. Finer Classification (Level 2): DEGURBA also offers a seven-class subclassification, where towns and semi-dense areas are divided into dense towns, semi-dense towns, and semi-dense areas (suburban/peri-urban areas), and rural areas are split into villages, dispersed rural areas, and very dispersed rural areas.

Development and Tools

The DEGURBA methodology was developed jointly by six organizations: the European Commission, the Food and Agriculture Organization of the United Nations (FAO), the United Nations Human Settlements Programme (UN-Habitat), the International Labour Organization (ILO), the Organisation for Economic Co-operation and Development (OECD) and The World Bank [43 (footnote 5)].

To support its implementation, technical tools like the Population-to-grid tool (GHS-POP2G), the Degree of Urbanization Grid (GHS-DUG) Tool, and the Degree of Urbanization Territorial Units Classifier (GHS-DU-TUC) have been made available. Furthermore, the European Commission, UNFPA, UN-Habitat, and the UN Statistics Division have supported capacity building and implementation workshops for national statistical offices.

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DEGURBA in the Context of WUP 2025

The WUP 2025 marks the twenty-second edition of global urbanization estimates published by the UN since 1963. The full integration of DEGURBA is the major methodological innovation of this revision.

Paradigm Shift and Dual Track Approach

Historically, urbanization estimates relied on data reported by national statistical authorities using country-specific definitions, which led to comparability challenges. The DEGURBA methodology was developed to overcome these limitations.

1. Urban-Rural Continuum: The new approach promotes a paradigm shift from the traditional urban-rural dichotomy to an urban-rural continuum.
2. International Comparability: DEGURBA provides rigorous and internationally comparable evidence on the changing distribution of the world's population. The consistency offered by DEGURBA is particularly valuable given the diverse urbanization trajectories observed across different national contexts.
3. Dual Track: Despite adopting DEGURBA, the WUP 2025 maintains a dual track approach, presenting estimates and projections derived from DEGURBA alongside those based on national definitions. This ensures that results based on national definitions remain available for domestic policy use and statistical continuity, even as DEGURBA improves international comparability.

Implications of Using DEGURBA vs. National Definitions

The choice of methodology profoundly impacts the assessment of global urbanization levels and trends.

• Level of Urbanization: Using DEGURBA, the world appears more urbanized than national statistics suggest. Aggregating estimates of urban population across disparate national definitions suggests that 58 per cent of the world's population lives in urban areas in 2025, which is well below the combined population of cities (45 per cent) and towns (36 per cent), totaling 80.5 per cent, according to DEGURBA.
• Treatment of Towns: National definitions often classify fewer settlements as urban, particularly in Central and Southern Asia and sub-Saharan Africa, where many settlements meeting the DEGURBA definition of "town" are classified nationally as "rural" areas. Conversely, in regions like Europe, Northern America, and Latin America and the Caribbean, national definitions align more closely with the combined population of cities and towns.
• Economic Development Correlation: The strong positive correlation traditionally observed between the level of urbanization and national income (when using national definitions) is far less evident when using the DEGURBA approach. This highlights that the connection between a country's development level and its population density may be mediated by factors associated with the national definition of urban space.
• Scope and Coverage: By lowering the minimum population threshold for cities from 300,000 in previous editions to 50,000, the WUP 2025, using DEGURBA, significantly expanded coverage to analyze over 12,000 urban settlements for 2025.

Data Limitations and Uncertainty

Despite its strengths, the implementation of DEGURBA faces challenges related to the underlying input data.

• Data Heterogeneity: Uncertainty in DEGURBA classifications stems from heterogeneity in the scale and resolution of the underlying administrative population data used to create the 1 km² population grids.
• Satellite Imagery Accuracy: Estimates based on satellite imagery, particularly data from before the 1990s (used for historical estimates), may have lower detection accuracy and thus greater uncertainty compared to more recent analyses.
• Backcasting: Estimates for the period between 1950 and 1975 were produced using back-projections, often informed by urban population based on country-specific definitions, due to the lack of widespread remote sensing imagery before 1975.

In essence, the Degree of Urbanization methodology acts as a universal ruler applied to human settlements, allowing the UN to measure demographic trends with clarity across continents, removing the distorting effects of localized national definitions, which vary dramatically—like using a single, globally accepted measure instead of relying on myriad country-specific yardsticks of differing lengths.

The sources, specifically the World Urbanization Prospects 2025 (WUP 2025), provide a comprehensive analysis of global population trends from 1950 to 2050, emphasizing the unprecedented shift of people into urban settlements and the critical role of the Degree of Urbanization (DEGURBA) methodology in measuring these changes consistently.

The data presented in WUP 2025 are estimates and projections for 237 countries and areas, and are consistent with the total populations estimated and projected according to the medium variant of the World Population Prospects 2024.

The Global Shift: Urbanization (1950–2050)

Urbanization is one of the most significant demographic shifts in human history, fundamentally altering how and where people live, work, and build communities. The sources highlight a dramatic increase in the concentration of people in settlements exhibiting urban characteristics (cities and towns) along an urban-rural continuum.

1. Population Distribution by Degree of Urbanization (DEGURBA)

The WUP 2025 uses the DEGURBA methodology to classify the global population into three categories: cities, towns (and semi-dense areas), and rural areas. This harmonized approach allows for rigorous and internationally comparable evidence on population distribution over time.

Settlement Type	Population Share in 1950	Population Share in 2025	Projected Population Share in 2050
Cities (Densely Populated Areas)	20% (approx. 500 million)	45% (of 8.2 billion people)	48.3%
Towns (Intermediate Density Areas)	40%	36%	34.6%
Rural Areas (Thinly Populated Areas)	40%	19%	17.1%
Total Global Population	2.5 billion	8.2 billion	Projected Total (Implied)

Source: [24, 47, Table A1] (Note: Percentages derived from World Urbanization Prospects 2025 data tables).

Key trends revealed by this classification (1950–2050):

• Cities became the most common living environment globally (overtaking towns and rural areas) sometime between 1996 and 2025.
• In 1950, city living was relatively unusual, with just 20 per cent of the world's population in cities. By 2025, cities were home to 45 per cent of the global population, more than double the 1950 proportion.
• The share of the global population living in towns has declined gradually, from 40 per cent in 1950 to 36 per cent in 2025, and is expected to fall slightly further by 2050.
• The population in rural communities has seen the steepest relative decline, falling by half since 1950 to just 19 per cent of the global population in 2025.

2. Future Growth and Peak Rural Population (2025–2050)

The sources project that global population growth will be overwhelmingly concentrated in urban areas:

• Two thirds of the world’s population growth between 2025 and 2050 will take place in cities, with most of the remaining one third concentrated in towns.
• The global rural population is expected to peak sometime during the 2040s and then begin to decline gradually.

3. Regional and Income-Group Trends

Global trends vary significantly by region and economic grouping:

• High-Income Countries: Urbanized earlier, achieving city-rural parity by 1957. They experienced the most significant city growth between 1950 and 1975, with more modest increases projected through 2050.
• Low-Income Countries (LDCs): Began from a much lower city population baseline (8 per cent in 1950) but have experienced the most dramatic urban transformation. LDCs achieved urban-rural parity much later (in 2017) and are projected to reach 40 per cent city population by 2050.
• Sub-Saharan Africa: In contrast to the global trend, this is the only region that has experienced substantial growth in its rural population over the past 75 years. Rural settings were predominant until 2012 when cities became more populous. Sub-Saharan Africa is the only region anticipated to have significant rural population growth over the coming decades.
• Central and Southern Asia: This region is the only one among the six analyzed where cities have not yet become the most common living setting as of 2025. Projections indicate that the population of cities could surpass that of towns around 2027.

4. The Impact of Built-Up Area Expansion

The sources also connect population trends to land use, noting that the expansion of built-up areas is outpacing population growth worldwide.

• Between 1975 and 2025, the extent of built-up area grew almost twice as fast as the global population.
• As a result, the average built-up area per capita rose from 43 square meters in 1975 to nearly 63 square meters in 2025. If trends continue, this average could rise to 74 m² by 2050.
• In most regions, the built-up area in cities expanded faster than the number of city dwellers, resulting in an increase in built-up area per capita for cities (from 31 m² in 1975 to 36 m² in 2025).
• However, in sub-Saharan Africa, the built-up area of cities has expanded more slowly than the city population has grown, causing the built-up area per capita in cities to decrease (from 46 m² in 1975 to 32 m² in 2025), which can signal increasing efficiency or, alternatively, crowding or slum conditions.

5. Concentration of Future City Growth

City population growth between 2025 and 2050 is projected to be highly concentrated:

• Seven countries (India, Nigeria, Pakistan, Democratic Republic of the Congo, Egypt, Bangladesh, and Ethiopia) are expected to add over 500 million city residents—accounting for over half of the projected increase in the global number of city dwellers during that period. These seven countries host nearly one third (30 per cent) of the global population in 2025.

The incorporation of the Degree of Urbanization methodology in WUP 2025 is instrumental in providing this comprehensive, comparable global overview. The shift from the traditional urban-rural dichotomy to an urban-rural continuum reveals that, based on the DEGURBA, the world appears more urbanized than national statistics suggest. For instance, DEGURBA indicates that 80.5 per cent of the world's population lives in cities (45 per cent) or towns (36 per cent), compared to only 58 per cent based on national definitions in 2025.

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The global population transformation discussed in WUP 2025 is akin to a slow-motion demographic landslide: over 100 years, the world's population centers have shifted from being roughly balanced between sparse rural areas and moderate towns, to predominantly high-density cities. While rural areas are not vanishing entirely, their relative demographic weight is rapidly being compressed as future growth concentrates almost entirely in the urban continuum.

The World Urbanization Prospects 2025 (WUP 2025) dedicates substantial analysis to the phenomenon of cities and megacities, framed by the rigorous, harmonized standards of the Degree of Urbanization (DEGURBA) methodology, which defines a "city" as an agglomeration with a density of at least 1,500 inhabitants per km² and a total population of at least 50,000 inhabitants.

The WUP 2025 integrates this new geospatial methodology to provide comparable data on all cities globally, moving beyond the diverse and often inconsistent national definitions used in previous editions.

I. The World's Cities: Distribution and Growth (1975–2050)

The sources detail the dramatic growth in both the number and population share of cities worldwide, particularly focusing on the role of smaller cities alongside megacities.

A. Expansion of City Coverage and Population

• Expanded Coverage: The WUP 2025 significantly expands its geographical coverage by lowering the minimum population threshold for cities from 300,000 inhabitants (used in previous editions) to 50,000 inhabitants. This change resulted in the analysis of over 12,000 unique cities globally in 2025, providing population estimates for each. This is a substantial increase from previous revisions (e.g., the 2018 revision covered close to 1,900 settlements).
• Historical Growth: The total number of cities worldwide more than doubled between 1975 (5,851 cities) and 2025 (12,140 cities). The share of the global population residing in cities grew from 31 per cent to 45 per cent over the same period.
• Future Projections: Projections indicate that by 2050, there could be more than 15,000 cities worldwide. Cities are expected to account for two thirds of the projected growth of the world’s population between 2025 and 2050.

B. The Dominance of Smaller Cities

Despite the attention given to the largest urban centers, the vast majority of the world’s cities are small or medium-sized, and they play a critical role in shaping sustainable urban development.

• Size Distribution (2025): Among the 12,000 cities identified in 2025, 96 per cent have fewer than 1 million inhabitants, and 81 per cent have populations below 250,000.
• Projected Distribution (2050): By 2050, most cities (over 12,000) are still projected to be relatively small, with populations below 250,000 inhabitants.
• Fastest Growth: The most rapid city growth (faster than 4 per cent per year between 2015 and 2025) is concentrated in these smaller settlements, with over two thirds of the fastest-growing cities having fewer than 250,000 inhabitants. These fast-growing smaller cities are predominantly located in sub-Saharan Africa (one third) and Central and Southern Asia (one quarter).
• Policy Needs: Smaller settlements often lack the planning capacity and resources required to manage their rapid growth sustainably. They need improved access to basic services, better land-use management, and increased connectivity.

C. City Growth Dynamics: Existing vs. Emerging Cities

Most city population growth occurs within existing cities, but a substantial portion comes from towns growing into cities.

• Existing Cities: Between 2000 and 2025, more than three quarters (77.4 per cent) of the 1.3 billion new city residents added globally lived in localities that were already classified as cities in 2000 [121, 127, Figure 2.3].
• Newly Emerging Cities: These are towns that grow to satisfy the minimum criteria to be considered a city. They are expected to account for a slightly larger share of total city population growth in the coming decades (28 per cent during 2025–2050) compared to the recent past (23 per cent during 2000–2025) [121, Figure 2.3].
• Regional Concentration of Future Growth: Growth between 2025 and 2050 will be concentrated in just seven countries (India, Nigeria, Pakistan, Democratic Republic of the Congo, Egypt, Bangladesh, and Ethiopia), which are expected to add over 500 million city residents [28, 77, Figure 1.5].

II. Megacities: The Largest Urban Centers

Megacities are defined as very large cities with a population of 10 million or more inhabitants. The WUP 2025 tracks their rapid multiplication and shifting global ranking.

A. Number and Location of Megacities

• Growth in Number: The number of megacities quadrupled from eight in 1975 to 33 in 2025.
• Population Share: The share of the world’s population residing in megacities increased from under 3 per cent to nearly 8 per cent between 1975 and 2025.
• Geographic Concentration: Over half of the megacities (19) in 2025 are located in Asia. India alone has five megacities, and China has four.
• Future Megacities (2050): The number of megacities is projected to rise to 37 by 2050. New additions projected to surpass the 10 million threshold include Addis Ababa (Ethiopia), Dar es Salaam (United Republic of Tanzania), Hajipur (India), and Kuala Lumpur (Malaysia).

B. Ranking and Population Dynamics of the World's Largest Cities

The ranking of the most populous cities is projected to change significantly due to uneven growth rates.

Rank (2025)	City	Population (2025, millions)	Projected Rank (2050)	Population (2050, millions)	Key Trend
1	Jakarta (Indonesia)	41.9	2	51.8	Projected to be overtaken by Dhaka.
2	Dhaka (Bangladesh)	36.6	1	52.1	Expected to become the world's largest city by mid-century.
3	Tōkyō (Tokyo) (Japan)	33.4	7	30.7	Population expected to shrink, falling from 1st in 2000 to 7th in 2050.
7	Al-Qahirah (Cairo) (Egypt)	25.6	6	32.4	The only city among the top ten in 2025 that is not located in Asia.
11	Karachi (Pakistan)	21.4	5	32.6	Expected to enter the top ten by 2030 and rank fifth by 2050 due to rapid growth.

Tokyo and Seoul (Republic of Korea) are the only cities among the ten largest in 2025 that are expected to experience a population decline by mid-century.

C. The Impact of the DEGURBA on City Assessment

The adoption of the harmonized DEGURBA definition provides a more consistent assessment of city size and growth compared to previous reliance on varied country-specific definitions.

• Inconsistent National Definitions: Historically, city size relied on country-specific definitions (e.g., administrative or broader metropolitan areas), leading to distorted comparisons. For example, the 2018 revision, using country-specific data, projected Jakarta’s 2025 population at just 12 million.
• Revised Assessment: Using DEGURBA in WUP 2025, Jakarta is ranked as the world’s most populous city in 2025 (42 million inhabitants). The previous national definition excluded many densely populated, contiguous communities captured by the DEGURBA.
• Similarly, the populations of Guangzhou (China) and Seoul (Republic of Korea) were estimated to be roughly twice as large by the DEGURBA compared to their country-specific definitions, substantially increasing their rank among the world’s largest cities.

III. City Challenges: Density and Land Use

The sources link city population dynamics to broader sustainability issues, specifically relating to population density and the expansion of built-up areas.

• City Density: Cities are characterized by high population density. In 2025, the world's most densely populated cities, such as Mumbai (27,000 people per km²) and Karachi (25,000 people per km²), were concentrated in Asia and Africa. Conversely, cities in the United States of America (e.g., Boston, Los Angeles) and Australia (e.g., Perth) were among the least densely populated large cities.
• Density Change: Population density increased between 2000 and 2025 in almost half of the world’s cities, particularly in Latin America and the Caribbean (79 per cent of cities) and sub-Saharan Africa (74 per cent of cities).
• Built-up Area Expansion: The extent of the built-up area in cities grew faster than the city population in most regions, causing the average built-up area per capita to rise (from 31 m² in 1975 to 36 m² in 2025). However, in sub-Saharan Africa, the built-up area expanded more slowly than the city population, causing the built-up area per capita to decrease (from 46 m² in 1975 to 32 m² in 2025).
• Implications of Density Change: Increases in density may reflect efficient, compact urban settlements or, if poorly planned, can indicate conditions of crowding or sprawl. For instance, the declining built-up area per capita in sub-Saharan African cities may point to crowding or slum conditions if infrastructure lags behind population growth.

The WUP 2025 highlights that while megacities represent the peak of urban concentration, the future of urbanization will be critically defined by the rapid growth and sustainable management of the thousands of smaller cities and towns, especially across Africa and Asia.

The World Urbanization Prospects 2025 (WUP 2025) extensively discusses spatial dynamics and land use, framing them as critical elements of sustainable urbanization and integrating this analysis through the use of geospatial methodologies like the Degree of Urbanization (DEGURBA) and the Global Human Settlement Layer (GHSL).

This focus goes beyond mere population counts to examine how human settlements occupy and expand across the physical environment, using key indicators such as built-up area per capita and population density.

I. Methodology: Geospatial Inputs for Spatial Dynamics

The WUP 2025's capacity to analyze spatial dynamics relies heavily on advanced geospatial methods:

1. Global Human Settlement Layer (GHSL): This project utilizes satellite imagery, including data from the Copernicus and Landsat programs, to map built-up areas and generate population grids (GHS-POP) at a 1 km² resolution. Built-up area (GHS-BUILT) is defined as any roofed structure erected above ground for human use (residential, industrial, commercial, etc.). Built-up areas are a physical manifestation of human settlements and serve as a key input for delineating settlements via the DEGURBA methodology.
2. DEGURBA and Spatial Classification: DEGURBA classifies areas into cities, towns (or semi-dense areas), and rural areas based on population size, density, and contiguity thresholds applied to these 1 km² population grids, ensuring consistent international comparison of spatial patterns.
3. Expanded Data Scope: The WUP 2025 provides land area and built-up area data for countries, regions, and over 12,000 individual urban settlements, allowing for new analyses examining the expansion of human settlements and their implications for sustainable development.

II. Global Trends in Built-up Area and Land Use Efficiency

The sources reveal a critical trend: the expansion of the physical footprint of human settlements is outpacing population growth globally.

A. Built-up Area Outpacing Population Growth

• Rate of Expansion: Between 1975 and 2025, the extent of the built-up area worldwide grew almost twice as fast as the global population.
• Built-up Area Per Capita: Consequently, the average built-up area per person increased significantly. In 1975, the average built-up area per capita was 43 m², rising to nearly 63 m² by 2025. If recent trends persist, this average could increase further to 74 m² by 2050.
• Sustainability Concern: When built-up area grows faster than population, resulting in an increase in built-up area per capita, it raises concerns about the efficiency and long-term sustainability of human land use patterns. Monitoring this indicator is key to achieving Sustainable Development Goal (SDG) 11.

B. Regional Differences in Land Use Efficiency

There are notable regional differences in how land is consumed:

• Highest Land Consumption: Populations in Europe, Northern America, Australia and New Zealand use the most land per capita for buildings and structures, occupying an average of 143 m² per capita in 2025, which is twice the global average.
• Lowest Land Consumption: Central and Southern Asia used the least built-up area per capita, at just 33 m² in 2025.
• Latin America and the Caribbean had the second highest built-up area per capita at 72 m².

III. Spatial Dynamics within Cities: Density and Crowding

Cities are analyzed for their density and land use efficiency, which provides insights into urban spatial development patterns and challenges.

A. City Density and Efficiency

• Cities are more land-efficient: Cities generally use land more efficiently than towns or rural areas because they concentrate the population geographically. In 2025, the world’s cities occupied an average of 36 m² of built-up area per city dweller, significantly less than the 63 m² global average across all settlement types.
• City Built-up Expansion: However, the collective built-up area of cities has grown faster than the global city population, causing the average built-up area per city dweller to rise from 31 m² in 1975 to 36 m² in 2025.

B. Regional Contrasts in City Density

Changes in density reflect whether cities are becoming more compact or experiencing sprawl:

• Sub-Saharan Africa (Decreasing Built-up Area Per Capita): In contrast to other regions, the built-up area of cities in sub-Saharan Africa has expanded more slowly than the city population. This caused the average built-up area per capita in cities to decrease from 46 m² in 1975 to 32 m² by 2025. While this could indicate increasing efficiency, the sources caution that declining built-up area per capita, especially when infrastructure lags behind population growth, can also point to crowding or slum conditions. For example, in Nairobi, Kenya, rapid population growth caused density to increase significantly, further complicating efforts to improve infrastructure in informal settlements.
• Fastest Density Increase: Latin America and the Caribbean saw 79 per cent of its cities increase in density between 2000 and 2025, and sub-Saharan Africa saw an increase in density for 74 per cent of its cities.
• Density Decline/Sprawl: In Central and Southern Asia and Eastern and South-Eastern Asia and Oceania, reductions in population density were more common than increases, suggesting a higher propensity for urban sprawl.
• Most Densely Populated Cities: The world’s most densely populated cities in 2025 had over 20,000 inhabitants per km², with examples including Mumbai (India) (27,000/km²) and Karachi (Pakistan) (25,000/km²).

IV. Implications for Sustainable Development and Urban-Rural Interdependence

The spatial dynamics and land use trends highlighted by WUP 2025 have profound implications for sustainability and planning.

A. Environmental Consequences of Land Consumption

• Agricultural Land Loss: Urban expansion results in the conversion of agricultural land, deforestation, habitat fragmentation, and biodiversity loss. Approximately 60 per cent of the land converted to urban space since 1970 was formerly productive farmland.
• Climate Impact: The expansion of the built environment contributes to environmental pressures, including approximately one third of global energy consumption and 75 per cent of global greenhouse gas (GHG) emissions from urban areas.
• Urban Sprawl: The unrestricted growth of built-up areas (urban sprawl) diminishes the efficiencies associated with urban density, leading to increased pollution, loss of habitat, and strain on infrastructure.

B. Integrated Land-Use Planning

The sources advocate for a policy approach that treats cities, towns, and rural areas as interconnected and interdependent spatial units.

• Compacting Growth: Given the environmental consequences, compact, connected, and coordinated growth patterns should be prioritized to curb sprawl, reduce emissions, and protect ecosystems.
• Towns as Connectors: Land-use strategies in towns must balance development needs with the preservation of agricultural and natural ecosystems, as towns act as critical nodes connecting rural populations to cities.
• Rural-Urban Linkages: Strengthening these linkages through investments in transport, digital connectivity, and infrastructure is key to reducing intraregional disparities and fostering balanced territorial development.

The WUP 2025 uses built-up area and density metrics as a vital diagnostic tool, shifting the focus from simply where people live to how they are organized in space, revealing whether urbanization is proceeding toward efficient, compact, and sustainable models, or toward sprawl and crowding. This analysis of spatial dynamics is crucial for guiding policies aimed at achieving SDG 11.

The World Urbanization Prospects 2025 (WUP 2025) frames its findings on global demographic and spatial changes within a robust discussion of policy implications, emphasizing the need for integrated planning, sustainable management of all settlement types, and the strategic use of harmonized data (like the Degree of Urbanization, or DEGURBA) to achieve global development goals.

The key policy implications discussed focus on leveraging urbanization for sustainable development, managing the growth of cities and megacities, supporting the vital role of towns and rural areas, and addressing environmental impacts.

I. Overarching Policy Mandates and Data Utilization

The core objective of the WUP 2025 report is to support evidence-based policymaking, planning, and monitoring.

• Global Frameworks: Policymaking must be guided by international agendas, specifically the Sustainable Development Goals (SDGs), particularly SDG 11 ("make cities and human settlements inclusive, safe, resilient and sustainable") and the New Urban Agenda. The WUP 2025 serves as an essential resource for those working to implement these goals.
• Integrated Planning Paradigm: Sustainable development requires integrated planning that treats cities, towns, and rural areas as interconnected and interdependent. This approach recognizes the roles of all settlement types and prioritizes compact, connected, and coordinated growth patterns to curb sprawl and protect ecosystems.
• The Role of Harmonized Data (DEGURBA): The integration of the DEGURBA methodology strengthens the analytical value of the WUP 2025, enabling a more nuanced representation of urbanization patterns and supporting internationally comparable evidence. While national definitions are essential for local context, the DEGURBA ensures policymakers can align local realities with global monitoring frameworks.

II. Policy Implications for Cities and Managing Urban Growth

Cities, as hubs of economic and social development, are pivotal for achieving sustainable development, but their rapid and uneven growth requires targeted policy responses.

A. Managing Growth and Decline

• Addressing Uneven Growth: Diverse city growth trajectories require urban policies that can address both expansion and contraction of city populations.
  • Growing Cities: These cities, especially in resource-constrained countries, must prepare to provide adequate and affordable housing, transportation, clean water, sanitation, and healthcare to more people.
  • Shrinking Cities: Cities facing population decline often require policies focused on maintaining essential services for fewer residents and adapting to changing economic conditions without relying on growth momentum.
• Focus on Key Growth Centers: Future global city growth is highly concentrated, with seven countries (including India, Nigeria, and Pakistan) expected to add over 500 million city residents between 2025 and 2050. The success or failure of urbanization in these key countries will profoundly influence global development outcomes.
• Policy Examples: Countries like Australia and Ghana have introduced national urban policies to enhance productivity, sustainability, and livability. Ghana’s policy, for instance, focuses on promoting spatially integrated development and has utilized a multilevel governance system (national consultation, regional monitoring, district implementation).

B. Addressing Inequality and Informal Settlements

• Informal Settlements (Slums): Informal settlements, which house over 1 billion people globally, epitomize the challenges of unplanned urban growth and inadequate policy response. Policies are urgently needed to upgrade slums by ensuring residents’ access to basic services, thereby reducing poverty and improving well-being.
• Density and Crowding: Where rapid growth occurs without adequate planning, increases in density may reflect conditions of crowding or sprawl. For instance, the decreasing built-up area per capita in cities in sub-Saharan Africa may indicate crowding or slum conditions if infrastructure lags population growth. Policy interventions, such as integrated planning strategies seen in Medellín, Colombia, aim to integrate informal settlements into city infrastructure, alleviating crowding pressures.

C. Climate and Environmental Resilience

• Mitigation through Density: High densities in cities offer opportunities to mitigate climate change by promoting efficient land use, lowering energy consumption per person, and enabling transportation systems that reduce reliance on automobiles.
• Vulnerability and Adaptation: Cities are highly exposed to climate risks (coastal flooding, extreme heat). Policy must focus on adaptive and mitigating measures, such as implementing coastal protections, using "smart city" digital technologies, planting urban forests, and retrofitting buildings to lower energy consumption.
• Built-up Area Expansion: Since the expansion of built-up areas is outpacing population growth worldwide, resulting in rising built-up area per capita, policies must prioritize compact, connected, and coordinated growth patterns to curb sprawl and reduce environmental pressures.

III. Policy for Towns and Rural Areas

WUP 2025 emphasizes that policymaking should not focus exclusively on major cities but must recognize the unique, complementary roles of towns and rural areas across the settlement continuum.

A. Policy for Towns (The "Missing Middle")

• Recognizing Towns' Role: Towns (and semi-dense areas) are home to more than a third of humanity and serve as critical connectors between rural areas and cities.
• Dedicated Attention: The DEGURBA methodology highlights the significant role of towns, implying they require dedicated attention and resources in national urban policies.
• Balanced Territorial Development: Proactive urban planning for towns can promote balanced territorial development, reduce pressure on large cities, and contribute to sustainable growth. Strategies must balance development needs with the preservation of agricultural and natural ecosystems.

B. Policy for Rural Areas and Linkages

• Addressing Rural Decline and Ageing: Many rural communities face growing pressures from population ageing and out-migration of youth seeking education and employment.
• Strengthening Rural-Urban Linkages: Strengthening these linkages through coordinated investments in transport, digital connectivity, infrastructure, and essential services, along with support for smallholder agriculture and rural enterprises, is key to reducing intraregional disparities and fostering shared prosperity.
• Food Security and Land Conversion: Urban expansion, often originating from adjacent towns and cities, converts agricultural land—approximately 60 per cent of land converted to urban space since 1970 was formerly productive farmland. Policies are needed to prevent urban encroachment on fertile soils to maintain food security.

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In essence, the policy implications derived from WUP 2025 data—and especially from the harmonized DEGURBA classification—call for a sophisticated, national-level policy toolkit that recognizes the full urban-rural continuum. It advocates for moving beyond a simple urban-rural binary by treating sustainable urbanization not merely as a consequence of development, but as a complex process requiring deliberate, integrated planning and investment across all settlement types to manage the twin threats of unchecked urban sprawl and rural decline.