With the launch of the European integration process after World War II, a new type of administration emerged which was neither an international organisation nor a national administration. Drawing on extensive archival records and oral history interviews, this book is the first comprehensive study of the High Authority of the European Coal and Steel Community (ECSC) and the Commission of the European Economic Community (EEC), and their personnel, the European civil servants. This administrative elite was to have a vital influence on the European integration process, devising and administering key European policies such as the Common Agricultural Policy. Katja Seidel combines administrative and biographical history and provides significant insights into the origins of Europe's supranational institutions and the administrative cultures that developed in them. She effectively shows how European administrative elites and supranational administrations are vital to understanding the process of politics in Europe. This book will be invaluable for scholars of politics, history and the development of European integration.