For sustainable cities, Africa needs planning Interview: Joan Clos, executive director of UN-Habitat, visiting the Kibera slum in Nairobi, Kenya

Africa’s cities are growing very rapidly. By 2009 some 395 million Africans — nearly 40 per cent of the continent’s population — lived in urban areas. That number is projected to triple to more than 1.2 billion, or 60 per cent of all Africans, by 2050. For the United Nations Human Settlements Programme — known as UN-Habitat — that growth represents a dual challenge: helping Africans to better harness the productive potential of their cities, but also to cope with the increased demands for municipal services and decent housing, so that more and more people are not obliged to crowd into impoverished slum areas. Joan Clos, a former mayor of Barcelona, Spain, and since 2010 the executive director of UN-Habitat, believes that tackling those challenges will above all require more systematic urban planning. Africa Renewal’s managing editor, Ernest Harsch, spoke with him at UN-Habitat’s headquarters in Nairobi, Kenya.