The past decade has seen significant changes in the humanitarian policy landscape. These relate to changes in the origins and dynamics of humanitarian emergencies in a context of deepening globalization, fragmentation of conflict dynamics and increasingly violent war economies. They also reflect major changes in the size and shape of international response to these crises, as they have become linked to wider agendas of conflict management, development and more recently counter-terrorism. Changes at both levels have posed significant challenges to traditional humanitarian principles. This paper, commissioned by the Government of Ireland, examines one aspect of these, namely the role of official humanitarian aid donors in upholding humanitarian principles.