This book reads, in part, as a conversation with self, deeply reflective, clear and helpful as Daniel Levine grapples with and explains the moral nature of peacekeeping. Hugely illustrative and rich. * Jakkie Cilliers, Executive Director, Institute for Security Studies, Pretoria office * Far and away the finest and clearest analysis of the ethical dimensions of this important peacebuilding tool written to date. Levine dives into long-standing issues of consent, impartiality, use of force, and civilian protection and comes up with novel insights and arguments of enormous appeal, logic, and practicality, while ensuring throughout a good theoretical grounding. I believe this book will prove a landmark in this field, an essential go-to for scholars and practitioners alike. * William Durch, The Stimson Center *