Fortna demonstrates that peacekeeping is an extremely effective policy tool, dramatically reducing the risk that war will resume. Moreover, she explains that relatively small and militarily weak consent-based peacekeeping operations are often just as effective as larger, more robust enforcement missions. Fortna examines the causal mechanisms of peacekeeping, paying particular attention to the perspective of the peacekept--the belligerents themselves--on whose decisions the stability of peace depends. Based on interviews with government and rebel leaders in Sierra Leone, Mozambique, and the Chittagong Hill Tracts in Bangladesh, Does Peacekeeping Work? demonstrates specific ways in which peacekeepers alter incentives, alleviate fear and mistrust, prevent accidental escalation to war, and shape political procedures to stabilize peace.