Book excerpt: A series of humanitarian tragedies in the 1990s (Somalia, Rwanda, Srebrenica, Kosovo) demonstrated the international community's failure to protect civilians in the context of complex emergencies. They were the inspiration for two norms of protection, Responsibility to Protect (R2P) and Protection of Civilians (POC), both deeply rooted in the empathy that human beings have for the suffering of innocent people. Both norms have achieved high-level endorsement: R2P from the 2005 World Summit and its Outcome document (Art. 138-140) and POC from a series of Security Council resolutions. The two norms of protection were instrumental in adopting the Security Council Resolutions 1970 and 1973 (Libya) and 1975 (Cote d'Ivoire) in the year 2011. Both norms raise concerns of misinterpretation and misuse. They both are developing--sometimes in parallel, sometimes diverging, and sometimes converging--with varying degrees of institutionalization and acceptance. This process is likely to continue for some time, with successes and failures enhancing or retarding that development. This book engages in a profound comparative analysis of the two norms and aims to serve policymakers at different levels (national, regional, and UN), practitioners with protective roles (force commanders, military trainers, strategists, and humanitarian actors), academics and researchers (in international relations, law, political theory, and ethics), civil society, and R2P and POC advocates.