States define who their citizens are and exert control over their life and movements. But how does such power persist in a global world where people, ideas, and products constantly cross the borders of what the states see as their sovereign territory? This groundbreaking work sets to examine and interprets such challenges to offer a new way of thinking about citizenship. Abandoning the sovereignty principle, it develops a new image of citizenship using the connectedness principle. To do so, it interprets acts of citizenship by following "activist citizens" across the world through case studies, from Wikileaks and the Gaza flotilla to China's virtual world and Darfur. Written by a leader in the field, this accessible and original work imagines citizens without frontiers as a politics without community and belonging, inclusion without exclusion, where the frontier becomes a form of otherness that citizens erase or create. This unique work brings forth a new and creative way to approach citizenship beyond boundaries that will appeal to anyone studying citizenship, social movements, and migration.