This book examines the political and legal challenges of regional governance of the 28 countries of the European Union and the 48 in the Council of Europe. The contributions, dilemmas, and moral hazards from this record of nearly seven decades of regional inter-governmental institutions has kept the peace, but produced episodes of crisis from overstretching jurisdictions, thematically and geographically. Polarization between nationalist and integrative forces has displaced the idealistic aspirations of prior decades to build the rule of law and deter violence. Academics and policy makers will learn from the various legal and political efforts to integrate supranational and inter-governmental agencies with national political systems.