The 2008 financial crisis that turned into a sovereign debt crisis in 2010 severely hit most European Union (EU) countries. Besides the economic effects, many countries have witnessed an increase in political disaffection and a loss of legitimacy of their political institutions with the discrediting of mainstream parties and the rise of extremist or anti-system political alternatives, while the EU witnessed a very significant decline in public support. In this context of legitimacy crisis of the European integration project, the analysis of the evolution of the attitudes of national political elites towards the EU is of particular interest: not only because national political elites have driven the development of the European integration process since its inception, but also because of their position as intermediaries between citizens and European institutions. Based on European comparative elite surveys conducted in the frame of the ‘Integrated and United? A Quest for European Citizenship in an Ever Closer Union’ (INTUNE) and the subsequent ‘European National Elites and the Crisis’ (ENEC) projects, the aim of this book is to explore the views of national elites, their variety and evolution, in order to understand the legitimacy and the future of the EU integration process, particularly during the critical juncture of the last few years (2007–2014).