Starting from an international, interdisciplinary and integrative perspective, the Summer Academy “Energy and the Environment” aims at elaborating and discussing different approaches to a sustainable supply of energy. Aside from traditional themes of environmental policy, such as the conservation of natural resources and a sectoral focus, attention is increasingly converging on the prevention of global climate change. Feasible solutions can only be developed by way of international cooperation, with close collaboration between different academic disciplines and representatives of science, policy, interest groups and the private sector. This collection of essays, titled “Instruments of Environmental Policy in Liberalized Energy Markets”, addresses the fundamental challenge of assembling a suitable mix of instruments to ensure sustainable energy policies. The individual contributions draw on economics, political science and the law to identify central features of a sustainable energy sector.