The 17th Biennale of Sydney succeeds spectacularly as an act of urbanism. At a time when the practice of creative urbanism in this city finds itself uncomfortably confined between the immobile sandstone cliffs of stodgy bureaucracy and the wiles of crony developers, the real deal is most welcome, even if it is only temporary. Aside from the quality of the art, which is surprisingly high, it is clear that the Biennale organizers and curator David Elliott have succeeded in a genuine act of Urban Doing, that jolly competitor to the familiar discipline of urban planning.