Since the early 1990's, refugee crises in the Balkans, Central Africa, the Middle East, and West Africa have led to the international spread of civil war. In Central Africa alone, more than three million people have died in wars fueled, at least in part, by internationally supported refugee populations. The recurring pattern of violent refugee crises prompts the following questions: Under what conditions do refugee crises lead to the spread of civil war across borders? How can refugee relief organizations respond when militants use humanitarian assistance as a tool of war? What government actions can prevent or reduce conflict? To understand the role of refugees in the spread of conflict, Sarah Kenyon Lischer systematically compares violent and nonviolent crises involving Afghan, Bosnian, and Rwandan refugees. Lischer argues against the conventional socioeconomic explanations for refugee-related violence-abysmal living conditions, proximity to the homeland, and the presence of large numbers of bored young men. Lischer instead focuses on the often-ignored political context of the refugee crisis. She suggests that three factors are crucial: the level of the refugees' political cohesion before exile, the ability and willingness of the host state to prevent military activity, and the contribution, by aid agencies and outside parties, of resources that exacerbate conflict. Lischer's political explanation leads to policy prescriptions that are sure to be controversial: using private security forces in refugee camps or closing certain camps altogether. With no end in sight to the brutal wars that create refugee crises, Dangerous Sanctuaries is vital reading for anyone concerned with how refugee flows affect the dynamics of conflicts around the world.