* Overweight and obesity are very common in Australian adults (56%) and children (27%). * Rates of overweight and obesity are snowballing and will place greater burdens on health services for the treatment and care of chronic diseases. * Prevention is urgently required from health, social and economic perspectives, but the response to date has been inadequate. * A long-term, sustained action plan starting with a focus on young people is needed. This should particularly address the “obesogenic” environments causing the epidemic. * Although whole-of-government action is required, support from and involvement by parents, carers, community leaders, healthcare professionals, teachers, childcare workers, urban planners, recreation managers, food manufacturers, employers, advertisers, and communicators is essential. * The health sector should take the lead, but success will only come from concerted and integrated action across the whole of society. * There are now signs of political commitment to addressing overweight and obesity. Doctors should get behind this and help mobilise community support.