Throughout the world, city planners and governments grapple with the challenges of urban planning using remarkably similar land use regimes. Yet the realisation is increasing that real urban problems – crime, decay, drug abuse, inequality, depression and alienation – are not easily solved by the classic devices of a strategic plan and a zoning map. Planning regimes are therefore in constant flux, as planners and governments adjust and experiment to address these problems, often with little awareness as to what they are trying to accomplish.