So what exactly determines the nature of a city? Is it the patterns of employment, the type of housing, or the public transport system? No, according to Australian architect David Sutherland, it is its smoking policy. In his home city of Melbourne, a ban on smoking in buildings has totally transformed the urban landscape, he says. In a city that tended to have austere pavements and all activities taking place indoors, every bar and restaurant now spills out onto the street, to allow smokers to indulge their favourite vice while consuming a glass of Australian Chardonnay or some Pacific Rim cuisine. The no-smoking rule has had more impact, Sutherland says, than any carefully planned urban initiatives.