In an age of terrorism and securitized immigration, dual citizenship is of central theoretical and political concern. The contributors to this timely volume examine policies regarding dual citizenship across Europe, covering a wide spectrum of countries. The case studies explore the negotiated character and boundaries of political membership and the fundamental beliefs and arguments within distinct political cultures and institutional settings which have shaped debates and policies on citizenship. The analyses explore the similarities and differences in the politics of dual citizenship, to identify the dominant terms of public debates within and across selected immigration and emigration states in Europe. The research demonstrates that policies on dual citizenship are not simply explained by different concepts of nationhood. Instead, concepts of societal integration, which may well be contested in a given polity, are extremely influential.