Over the last fifteen years, policy and debate on development education have become increasingly framed in terms of citizenship. Yet, despite its ubiquity, citizenship is rarely defined. It remains unclear what exactly it means to be an ‘active citizen’, much less a globally engaged one. Drawing from the rich body of theory and debate within the social sciences in this field, in this article I highlight both the limitations and the opportunities posed by different understandings and deployments of ‘citizenship’ by a range of actors and interests. Exploring the multiple exclusions and inequalities experienced by particular groups which limit and/or inhibit their agency as active citizens, I argue that citizenship, within development education and more broadly, is not something which just exists; it must be claimed. Such claims involve struggles and tensions. In short, they involve activism.