This week, we’re talking about one of the biggest problems facing the developing world today. Untold millions are moving from country to cities in Africa, Asia and Latin America, in search of a better life – but with a few exceptions, those cities are not building the infrastructure those new arrivals require. So, what to do?

Luckily, we have an expert on hand to tell us. Sarah Colenbrander is an environmental economist currently working at the International Institute for Environment & Development (IIED). She tells me why the urban poor are growing in absolute terms, albeit not as a proportion of the world’s population; why their numbers have proved so difficult to measure; and what national and local governments can do to tackle the problem. She also tells me why things are going well in Brazil and Ghana – and not so well in Kinshasa.

The episode itself is below. You can subscribe to the podcast on AcastiTunes, or RSS. Enjoy.

Skylines is supported by 100 Resilient Cities. Pioneered by the Rockefeller Foundation, 100RC is dedicated to helping cities around the world become more resilient to the physical, social and economic challenges that are a growing part of the 21st century.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.

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