In <i>Radical Cities</i>, Justin McGuirk travels across Latin America in search of activist architects, politicians and radical communities. From Chile to Brazil, and from Mexico to Argentina, McGuirk discovers people who have begun rebuilding and redesigning their environments in radically new ways.<br><br>An architect in Chile has designed a new form of social housing where only half of the house is built, allowing the owners to adapt the rest; Medellín, the murder capital of Colombia, has been transformed with innovative public architecture; squatters in Caracas have taken over a 45-story skyscraper, Torre David; and architect Jorge Mario Jáuregui has upgraded Rio's favelas in exciting new ways.<br><br>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 urbanized 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, and together they are testing new ideas that the rest of the world can learn from.