International organizations are ubiquitous in contemporary Europe and the wider world. This book is the first systematic assessment of the interactions of the European Communities (EC) with other Western organizations like NATO, the OECD and the Council of Europe for the period from the late 1960s to the early 1990s. Based on fresh archival research, its various contributions explore forms of co-operation and competition between these forums and thus seek to ‘provincialize’ and ‘de-centre’ the role of the predecessors of today’s European Union. Drawing on examples from a diverse set of policy fields including human rights, the environment, security, culture and regional policy, the book argues that inter-organizational dynamics are crucial to understand why the EC became increasingly hegemonic among the organizations active in governing Europe. In other words, the EU would not be what it is, were it not for the dynamics analyzed in this book. This book was originally published as a special issue of the European Review of History.