The environment is not usually viewed as the most important problem in war-torn societies. 1 Humanitarian relief, security, economic reconstruction, and political reconciliation all command attention as urgent priorities. Yet violent conflict does extraordinary damage to the environment on which people depend for their health and livelihoods; human insecurities in such settings have a strong, immediate ecological component as people struggle for clean water, sanitation, food, and fuel in a context of conflict-ravaged infrastructure, lost livelihoods, and disrupted institutions. Over time, more diffuse but equally important environmental challenges emerge: establishing systems of environmental governance, managing pressures on the resource base, creating administrative capacity, dealing with environmental effects of recovery, and finding sustainable trajectories for reconstruction. The scholarly debate over whether environmental degradation causes violent conflict is ongoing. But as the chapter shows, a growing body of scholarly literature and case documentation indicates that the failure to respond to environmental needs of war-torn societies may greatly complicate the difficult tasks of peacebuilding. At worst, tensions triggered by environmental problems or contested access to natural resources may lead to renewed violent conflict; more generally, failure to meet basic environmental needs undercuts reconciliation, political institu tionalization, and economic reconstruction. In the short run, failure to respond to environmental challenges can deepen human suffering and increase vulnerability to natural disasters. In the long run, it may threaten the effective