Ratification politics involves the set of procedures by means of which the European Union Member States accept changes to EU primary law / the EU constitution. These procedures offer a wide structure of political opportunities which actors: parliamentary groups and political parties; social movements; governments and court etc., seize and use in order to influence and shape the result. This book focuses on the politics of ratification of EU Treaties and reviews the processes of ratification of EU primary legislation. Research and academic debate on EU constitutional politics have almost exclusively focussed on negotiation of new treaties and their institutional setting. In contrast with this interest, research has neglected ratification as a very important stage in EU constitutional politics. As the EU Constitution has proved, the ratification process may have deep effects unforeseen during the processes of negotiation. Moreover, the ratification stage produces some of the most intense debates on national membership of the EU and the EU itself. The author examines the process of ratification in a number of detailed cases including, the Treaties of Rome and Paris, the SEA, the Treaty of Maastricht, the Treaty of Amsterdam, the Treaty of Nice and the so far, failed EU constitution. This book will be of interest to students and researchers of European Studies, European Union studies, European Union Law and European Union Politics.