Urbanization and Rural-Urban Migration: Theory and Policy

Cities are becoming central to the global economy, but rapid urbanization leads to challenges like slums. Strategies must improve public services in rural areas to manage urbanization effectively.

Overview of Urbanization

Focus on rural-to-urban migration in Africa, Asia, and Latin America.
World population expected to reach 9.6 billion by 2050, with most growth in developing-world cities.
In 2009, urban population (3.42 billion) surpassed rural population (3.41 billion) globally.
Examines the role of cities in economic development and the rural-urban labor transfer model.
Evaluates policy options to moderate rural-to-urban migration and address urban unemployment.
Aims to harness the dynamism of developing cities for inclusive economic development.

Urbanization Trends and Living Conditions

The developing world is expected to become majority urban before 2020.
Most urban growth is occurring in Asia and Africa.
- Africa's urban population is projected to grow from 414 million in 2012 to over 1.2 billion by 2050.
- Asia's urban population will grow from 1.9 billion to 3.3 billion.
- Asia and Africa will account for approximately 86% of the global urban population increase.
- Rural population in Asia will decline due to rural-to-urban migration (Figure 7.1).
Urbanization rates increase when urban population growth exceeds rural population growth.
A positive association exists between urbanization and per capita income.
- More developed countries have a larger share of the population in urban areas (Figure 7.2).
By 2030, there will be almost 5 billion urban dwellers, nearly five-eighths of the projected world population.
Today's poorest countries are more urbanized than today's developed countries were at a comparable development level.
Urbanization continues in nearly all developing countries, even with minimal industrialization (Figure 7.3).
Urbanization occurs at varying rates, influenced by domestic policies.
Significant demographic phenomenon: rapid growth of cities in developing countries.
- In 1950, 275 million people lived in developing-world cities.
- By 2010, the world's urban population surpassed 3.4 billion.
- Over three-quarters of urban dwellers live in metropolitan areas of low- and middle-income countries.
Shares of urban population in Africa are being reached at lower levels of per capita income than in developed countries.
Urbanization in Africa is not associated with industrialization.
Sheer numbers of people moving into cities are unprecedented due to larger populations.
The sizes of individual cities are very large at low income per capita levels.
Most developing-country urban growth is in cities of less than 5 million people.
Population growth in cities over 5 million is more rapid than in smaller cities.
By 2025, only about half the urban population will be in cities with less than a half million people.
The developing world dominates the world's largest cities, including megacities (Figure 7.4).
In 1970, there were only 2 megacities; by 2011, there were 23.
By 2025, 30 of the 37 megacities will be in developing countries.
Small and medium cities in developing countries have added more residents than megacities.
The number of people in megacities will increase 16 times from 1970 to 2025 (Figure 7.5).
Megacities could offer agglomeration economies, but congestion costs may rise rapidly.
Megacities tend to be more capital intensive and may have outsized social and health problems.
Almost all increments to the world's population will be accounted for by urban areas (Figure 7.6).
A key question is how cities will cope economically, environmentally, and politically.
Cities offer agglomeration economies, economies of scale and proximity, and economic and social externalities.
Social costs (housing, services, crime, pollution, congestion) can outweigh urban advantages.

Urban Bias

Rapid urbanization and urban bias in development strategies lead to growth of slums and shantytowns.
One billion people live in urban slum settlements.
Figure 7.7 shows annual growth of urban and slum populations in 1990-2001 period.
Sub-Saharan Africa is the most rapidly urbanizing region, with most growth in slums.
Target 11 of Goal 7 in the Millennium Development Goals (MDGs) aims to improve lives of 100 million slum dwellers by 2020.
Simple extrapolation would point to a slum population of 3 billion people in 2050.
Misguided urban-planning policies and outmoded building codes contribute to the problem.
- Colonial-era building codes in Nairobi, Kenya, made it impossible to build an