How should the international community act in the face of genocide and humanitarian atrocities? Evans, a former Australian foreign minister, is one of the leading intellectual forces behind the doctrine of "the responsibility to protect," a landmark effort to redefine the norms of sovereignty and interventionism, endorsed by the UN World Summit of 2005. This book provides a grand statement of the idea and describes the troubled world setting in which it emerged and its far-ranging implications. The innovation of the doctrine was to shift the debate from the international community's "right to intervene" to the obligations of states to protect their own people. The norm of state sovereignty is not absolute; when states fail in their duty to safeguard the lives and well-being of their own people, the outside world has a legal and ethical standing to act. The notion of a responsibility to protect is still widely debated, and Evans is at pains to point out the misconceptions of its opponents. He stresses that the doctrine is aimed primarily at establishing not a normative foundation for coercive military intervention but rather a sustained commitment by the international community to work with weak states to prevent the outbreak of mass atrocities. Much of the book is an elaboration of the tools and strategies that are available to intervening states before, during, and after crises break out. The debate on when and how the world should act in humanitarian crises will continue -- and this inspired manifesto will be its essential guidebook.