Rapid urbanization, a by product of the process of economic growth, is a pervasive phenomenon in the developing world. The share of urban population has, in the last quarter of a century, grown from about one fifth to over one-third; and populations of such metropolitan centres as Mexico City, Calcutta and Bombay compare in size with the national populations of several small and medium sized countries.
The pace of urban growth is also indicated by the fact that while in 1950 only one city in the developing countries had a population exceeding 5 million, some forty cities are expected to be at or above this size by the year 2000. Such a rate of growth presents innumerable challenges for national and local policymakers, particularly in the areas of urban employment, transport, housing, health and education.
