This study provides a comprehensive discussion of all aspects of the European Union presence in International Organisations (IOs). The editors seek to explore both the political and institutional implications of the EU's interaction with IOs and the effect of the EU's presence on the functioning of the respective IOs. The result of an international workshop with an outstanding line up of experts, the book discusses a range of issues, including the Impact of the EU security contributions to IO's such as the OSCE, NATO and the UN, and the EU's role in decision making; the role of EU - US relations in the development of major International Organisations; participation in the Doha Development agenda and the EU's relationship with the WTO; the issues of leadership and coherence within and outside the EU; and the growing international relationship with the African Union and the more troubled supporting role of the Commonwealth. Approaching the EU's international interactions from different theoretical and analytical angles, this work clearly discusses the broad spectrum of issues that surround the evolution and future of the European Union in an international context.