No development in European integration has aroused greater interest or greater controversy in recent years than the Open Method of Co-ordination (OMC), which has become an increasingly broadly applied instrument of EU governance since its invention as part of the «Lisbon Strategy» in 2000. Yet it is widely agreed that the debates surrounding the OMC suffer from a serious empirical deficit. This book, based on an international research network organised by the University of Wisconsin-Madison, the Observatoire social européen, and the SALTSA Programme, focuses on two highly developed OMC processes, the European Employment and Social Inclusion Strategies, concentrating on their operation and influence at national and subnational levels. It comprises a combination of national and comparative studies, covering eight countries (Denmark, France, Germany, Ireland, Italy, the Netherlands, Sweden, and the United Kingdom) and four transversal themes (hard and soft law, participation, gender equality, activation). These studies are framed by a historical overview of the OMCs place in the construction of Social Europe, and by a synthetic conclusion, which assesses the available evidence on the OMC in action, and proposes a reflexive reform strategy for realising its theoretical promise as a new mode of EU governance.