This volume provides the most comprehensive study of the Responsibility to Protect (R2P) principle, and presents an authoritative and comparative examination of the emergence of this principle. The Oxford Handbook of the Responsibility to Protect (R2P) is a substantial work of scholarship. The editors have gathered together 53 articles that cover most aspects of this nascent political doctrine, across the spectrum from theory to practice. The collection will be of significant interest to politicians, diplomats, civil society actors and academics practising in the spheres of international law and international relations. At more than 1,000 pages, it is likely to become the initial comprehensive reference for anyone interested in a serious study of the prevention of mass atrocity crimes.