The world’s population growth in coming decades will be predominantly in urban Asia and Africa. With about half of the world’s population now urban, the salience of the rural-urban dichotomy is declining: urban densities are decreasing; polycentric regions are on the rise; and the cultural, social and economic distinctions between rural and urban are increasingly blurred.
Nevertheless, urbanisation provides critical opportunities and challenges for sustainable development. Urbanisation and economic growth have combined to create various global environmental pressures, and often bring social and economic inequalities. However, dense urban settlement has environmental advantages, and measures to inhibit urbanisation often exacerbate inequalities.