Critics of federalism have long pointed to overlap and duplication as evidence of a system under pressure. This article challenges their critique through an examination of Australia's environmental assessment and approval regime. It finds that, in their quest to eliminate duplication and overlap, policy makers have imposed artificial divisions on a complex policy domain. By limiting the opportunities for political engagement, they have also surrendered some of the strengths of a federal system of government and removed important failsafe mechanisms which provide valuable insurance against policy failure. While the empirical argument is based on the Australian experience, the analysis has more general implications for federations characterized by concurrency.