Humanitarians are no longer simply seen as selfless angels. Their motivations and mastery, their principles and products are contested from inside and outside of aid organizations. Understanding the ongoing transformations in contemporary humanitarianism requires examining the nature and evolution of the dominant humanitarian culture away from an agreed culture of cooperation to a contested one of competition. In the post-Cold War era, the latter reflects militarization, politicization, and marketization. What is required is a learning culture for practitioners and a consequentialist ethics more oriented to responsible reflection than rapid reaction.