In the United States, defining what it means to be a citizen is central to discourse about immigration, naturalization, and identity politics. Although the concept of European citizenship is more tenuous, European countries wrestle with equally profound questions. Can European citizenship be constructed? Can democratic institutions thrive in Europe without a robust concept of citizenship? This insightful volume examines the rights and duties of citizens in liberal democracies-and the policy impact of citizenship debates-in both the United States and abroad.