This book provides a balanced introduction to diverse political economy perspectives on different aspects of European integration, demonstrating both the importance and the potential of research in this area. The volume includes three types of chapters: broad literature reviews, narrower applications of existing arguments, and new syntheses of competing claims. The authors also present a critical appraisal of how scholars in the EU and US use theory to understand European integration, and examine issues such as citizens' attitudes, perceptions and preferences of actors, the role of non-state actors, principle-agent questions, and the role and the autonomy of European institutions.This empirically informed and methodologically rigorous volume will be of great interest to students and researchers in the fields of comparative political economy, EU studies, international political economy and international organizations.