In settings of conflict and displacement, the provision of appropriate mental health services is essential. While most mental health research has focused on identifying rates of post-traumatic stress and other common disorders in post-conflict settings, there has been little recognition of substance abuse as both a cause and consequence of mental health problems. Problems that arise when people begin to abuse substances to cope with the severe stress of emergency situations include the depletion of finite family and community resources, violence, exploitation, neglect of children and other protection threats. As a case in point, refugee camps on the Thai-Burma border have become a fertile breeding ground for drug and alcohol addiction. A more inclusive view of global mental health--one that addresses the problems of substance use in post-conflict and displacement contexts--will better enable health professionals to make meaningful contributions to conflict resolution and longer-term peace-building processes.