In the face of the world's disorders, moral concerns have provided a powerful ground for developing international as well as local policies. Didier Fassin draws on case materials from France, South Africa, Venezuela, and Palestine to explore the meaning of humanitarianism in the contexts of immigration and asylum, disease and poverty, disaster and war. He traces and analyzes recent shifts in moral and political discourse and practices -- what he terms "humanitarian reason"-- and shows in vivid examples how humanitarianism is confronted by inequality and violence. Deftly illuminating the tensions and contradictions in humanitarian government, he reveals the ambiguities confronting states and organizations as they struggle to deal with the intolerable. His critique of humanitarian reason, respectful of the participants involved but lucid about the stakes of which they have lost sight, offers theoretical and empirical foundations for a new political and moral anthropology.