Ever since the mid twentieth century, when modernist utopia went to Latin America to die, the continent has been a testing ground of radical ideas in city-making. Here, in the most urbanised continent on the planet, extreme cities have bred extreme conditions, from vast housing estates to sprawling slums. But after decades of political and architectural failure, a new generation has returned to the problems of the city to address the poverty and inequality. This is a generation of activists, pragmatists, and social idealists who, together, are testing new ideas from which the rest of the world can learn.

Justin McGuirk is a writer, critic, and curator based in London. He is the director of Strelka Press, the publishing arm of the Strelka Institute in Moscow. He has been the design critic of The Guardian, the editor of Icon magazine, and the design consultant to Domus. In 2012 he was awarded the Golden Lion at the Venice Biennale of Architecture for an exhibition he curated with Urban Think Tank. His book, Radical Cities: Across Latin America in Search of a New Architecture will be published by Verso in spring 2014.