Thousands of organisations around the world are doing all they can to protect children, but many more are putting them at risk—and there is no single international legal framework or justice system to hold them to account. Up to 1 billion children live in territories affected by armed conflict; millions are killed or disabled as a consequence of war and many more are at extreme physical and emotional risk. Humanitarian disaster and conflict have forced 50 million children to flee their homes, with many experiencing horrifying levels of sexual exploitation and abuse. In these most fragile contexts, perpetrators can easily go unpunished. Children already in desperate and terrifying situations are at grave risk of being harmed by the same soldiers and civilian staff sent to protect them. In crises across the world, humanitarians and peacekeepers have subjected children to rape, trafficking, violence and abuse, demanding sex in exchange for the basics of survival--food, shelter, education and medicine. Too often, children have no way of reporting the abuse, no access to medical or psychosocial care, and no recourse to justice. Peacekeeper, Humanitarian, Abuser explores how and why these abuses occur, and proposes a robust, evidence-based solution for safeguarding children.