Fifty years since the inception of European integration, political scientists are increasingly attracted by the theoretical and empirical puzzles of how to establish if and how the EU has changed representation, governance and public policy in the member states and beyond. Broadly speaking, this is the domain of Europeanization research. In this chapter, we first make the argument that the concern with Europeanization is somewhat in the genes of the academic study of European integration. In a sense, this field of research has always existed. But in another sense, Europeanization as a distinct research field is increasingly prominent, as shown by several literature reviews and internet sites² dedicated to this topic (Olsen, 2002; Börzel and Risse, 2003; Graziano and Vink, 2007; Lenschow, 2005; Axt et ai, 2007; Schimmelfennig, 2007).