A national approach to environmental protection is the most effective way for Australia to protect its own environment and to contribute to the common cause of global environmental protection.[1] The centerpiece of this approach should be a federal environmental protection authority (EPA), able to deal with the issues which arise on a transboundary basis, both nationally and internationally. However, the powers of a national agency will need to be tailored to avoid conflict within the system of cooperative federalism in Australia. This article reviews constitutional tensions between federal and state government as they relate to several of the major international environmental conventions that bind Australia. The authors conclude that a federal authority, committed to enforcing Australia's international agreements to protect the environment, is the most effective means of addressing worldwide concern with the state of the natural world.