Little is known about how immigrants participate in politics and whether they transform political engagement in contemporary democracies. This study investigates whether citizenship (as opposed to being foreign-born) affects political and civic engagement beyond the voting booth. It is argued that citizenship should be understood as a resource that enhances participation and helps immigrants overcome socialization experiences that are inauspicious for political engagement. The analysis of the European Social Survey data collected in nineteen European democracies in 2002-03 reveals that citizenship has a positive impact on political participation. Moreover, citizenship is a particularly powerful determinant of un-institutionalized political action among individuals who were socialized in less democratic countries. These findings have important implications for debates over the definition of and access to citizenship in contemporary democracies. Copyright © 2011 Cambridge University Press.