The overall aim of this paper is not to present any answers, but to hopefully stimulate some questions about change in the Australian structure of cities at the present time. City structure is an outcome of many diverse processes – labour markets, housing markets, governance, infrastructure and planning, taxation and investment, transport and mobility and so on – rather than a process in itself. At best, I can only hope to pull together some of the key themes that seem to be emerging from the literature and research on Australian cities over the past few years. Much remains to be answered, hence the calls for more research that pepper this paper. But this much is certain: Australian cities are growing and maturing, and in so doing are evolving into very different entities than they were thirty years ago, reflecting profound changes in the social, economic and cultural drivers that produce and shape urban areas. These changes offer major challenges for those charged with the effective management of our urban areas.