The number of cities in China increased from 132 in 1949 to 655 in 2009, with most of the changes having occurred in the last 30 years. The most important drivers of rapid urbanization are economic growth and industrialization. As it would be predicted by the venerable Lewis model, rural labor, mainly from western China, has migrated to cities, mainly in the export-intensive eastern coastal regions. Government agencies are unable to provide precise migration estimates. However, it appears that roughly 150 million migrants move from rural areas to urban areas for work each year. The urbanization rate, now 47%, may reach about 60% by 2020 and 75% by 2050.

Urbanization has greatly changed the lifestyle of the Chinese people and the geographic distribution of population. It is a locomotive for economic growth but also has implications for water supply, transportation, environmental protection, and consumption of natural resources. More than 100 cities suffer from severe fresh water shortages. Traffic jams associated with urbanization, the growing motor vehicle fleet, and lags in infrastructure development seriously affect the daily life of many millions. In some cities, air pollution has been shown to cause significant health problems. Even the basics of urban management, such as waste disposal, have become headaches familiar to urban decision makers.

The Chinese government has paid great attention to the healthy development of cities. In recent years, over a thousand urban wastewater treatment plants have been built. About two-thirds of garbage collection and treatment meets standards of good international practice. By the end of 2008, the coverage rate in urban areas reached 37%. Local governments have made great efforts to increase the use of coal gas and natural gas, with a coverage rate of 90% in cities. Large-scale public transportation including the underground, elevated railway and traditional public transport systems are expanding quickly in many cities.

From a strategic point of view, China aims for the harmonious development of urban and rural areas. We encourage the development of modern villages and small towns with better facilities for economic development and quality of daily life. The low-carbon and green city models are encouraged. By the end of 2020, the target is that emissions of CO2 per unit of GDP will have been reduced by 40–45%, mainly in cities. Out of 612 cities being monitored by environmental agencies, air quality reached Class 2 and above in 504. Only 8 cities were ranked below Class 3. A social assistance system to alleviate poverty in urban areas has been established, and social protection reforms are attempting to address the issue of rural poverty and the rural–urban gap.

China, a major player on the international stage, is still on the road to development at home. At present, the government focuses on two targets. The first is transition from heavy resource consumption and environmental pollution to a resource-saving and environment-friendly mode of economic growth. The second is transition from a labor-intensive, centralized economy to a knowledge-based, innovative economy. Urbanization will continue at a fast pace, and China is committed to ensuring that it is, at the same time, healthy and sustainable. I hope this important special issue of the prestigious international journal Population and Environment, born in a unique collaboration between the Institute for Population Research at Peking University and the International Institute for Applied Systems Analysis outside Vienna, will help readers to understand better the achievements and challenges of urbanization in China.