Since the Second World War a historically unprecedented set of international institutions – NATO, the EU and the OSCE – have become a central feature of Europe’s security landscape. The nature of these institutions and their impact on European security, however, are still not adequately understood. Realist and inter-governmentalist theories suggest that international institutions are the products of competing preferences and relative distribution of power amongst their member states. Contra such theories, this paper will explore how far NATO, the EU and the OSCE amount to more than the aggregate preferences of their member states, whether and how these institutions shape the preferences and identities of their member states and how far these institutions have the capacity to shape outcomes independent of their member states. The paper will employ an institutionalist, primarily historical institutionalist, theoretical perspective and provide a comparative analysis of NATO, the EU and the OSCE.
