World Population Challenges

Cities and urban areas are gaining an estimated 60 million people per year - over 1 million every week. In many developing countries cities are growing two or three times faster than the overall population. As urban areas - particularly smaller towns and cities - continue to grow in size, about 5 billion people are expected to live in cities by 2030 - about 61 per cent of the global population of 8.1 billion, the UN projects.

Overview by Don Hinrichsen in "People & the Planet"