A wide range of non-state actors, such as civil society organisations, social movements, ‘community-based’ organisations and non-state armed actors can play a key role in social change at different scales. Factors such as the development of digital information and communications technologies, conflict, and the emergence of ‘global’ development challenges that transcend nation state boundaries may increase the importance of non-state actors in certain contexts. Such actors might challenge the status quo, but can also be co-opted by states, international organisations and other political actors, calling into question our assumptions about boundaries between ‘state’ and ‘non-state’ and ‘formal’ and ‘informal’ institutions.