The European Union (EU) poses quite profound questions for scholars and students of the social and political sciences. This benchmark Handbook is designed to provide an authoritative state-of-the art guide to the scope of the field suitable for both established scholars and students of the EU; reflect and contribute to the debates about the nature of the field of EU studies and EU politics in particular; and explore in detail the development of the many approaches to the study of EU politics. Divided into four sections, the Handbook focuses on theorizing European integration; the EU as polity; politics and policy making in the EU; and the EU and the international system.