This book explores conceptual and operational questions regarding the development and implementation of the Responsibility to Protect. The mass atrocity norm known as the Responsibility to Protect (R2P) has enjoyed meteoric success since the concept was introduced in 2001. But perhaps precisely because of how quickly the concept secured its privileged place in the pantheon of ideas and concerns in international affairs, many fundamental questions remain concerning its origins, its conceptual contents, and its relevance to actual cases of mass atrocity. This book seeks to explore that terrain by drawing together a group of scholars diverse enough to engage with the complex array of political, legal and ethical questions raised by R2P. Critical questions raised here include: What are the limits of the authority that R2P confers on international actors? What does the evolution of R2P mean for North-South relations? Just how significant is R2P in the context of the broader human rights landscape? In addition to those conceptual and theoretical matters, special attention is given to the operational context in which the meaning of R2P is ultimately rendered. As events in Africa have figured so significantly into the norm’s development, the contributors pay special attention to the problems and prospects of mass atrocity prevention in that context. This volume will be of much interest to students of the Responsibility to Protect, war and conflict studies, peacebuilding, international law, and IR/Security Studies.