This study examines the associations between alcohol and other drug problems (AOD) and post-traumatic stress disorder (PTSD) symptoms in 499 women recruited from outpatient treatment programmes for AOD problems and the general community in western New York. The women were divided into three groups: no-AOD, past-AOD, and current-AOD. The current-AOD group was further subdivided into groups based on alcohol, marijuana, and cocaine misuse. Group comparisons on PTSD symptoms revealed that the current-AOD group experienced more PTSD symptoms than the no-AOD and past-AOD groups. The alcohol and cocaine misuse groups experienced more PTSD symptoms overall and for each symptom cluster than the no-AOD and past-AOD groups, but did not differ from each other or the marijuana group on PTSD symptoms. These findings suggest that individuals who have AOD problems should be assessed for PTSD symptoms and provided with trauma-specific interventions when warranted. Trauma-informed care may benefit those in AOD treatment. Individuals who have PTSD symptoms should be assessed for AOD problems as well.