Ailish Johnson examines national welfare state regimes of EU Member States and the features of the European Union and the International Labour Organization that encourage cooperation and assure outcomes of supranational cooperation higher than theories of inter-state bargaining or social dumping would predict. By tracing the development of EU and global social policy from the 1950s to today, she identifies policy leaders, resisters and passive states. She concludes with an analysis of the forms and outputs of supranational social policy and suggests limits of social policy in an enlarged European Union.