Early childhood traumatic experiences, such as childhood maltreatment, are associated with an enhanced risk of adolescent and adult alcohol and substance use disorders (defined as DSM-IV alcohol or substance abuse or dependence). Maltreated children and adolescents manifest dysregulation of major biological stress response systems including adverse influences on brain development. Dysregulation of biological stress response systems may lead to an enhanced vulnerability for psychopathology, particularly posttraumatic stress disorder (PTSD) and depression. These negative affect disorders may put a child at increased risk for adolescent or young adult onset alcohol or substance use disorders. Thus, studies in developmental traumatology may prove to be critical in the effort to attempt to link the neurobiology of maltreatment-related PTSD with the neurobiology of alcohol and substance use disorders and in developing early strategies for the prevention of adolescent and adult alcohol and substance use disorders.