This research was conducted with 96 low-income pregnant women who enrolled in a residential substance abuse treatment program. The study had three goals: (a) to document the prevalence of exposure to violent trauma, (b) to examine the prevalence of posttraumatic stress symptomatology, and (c) to assess if trauma exposure and posttraumatic stress were related to program completion. Results indicated that the sample had high rates of exposure to violent trauma, as 72% had experienced sexual assault, 67% had experienced physical assault, and 68% had experienced indirect violent trauma. High rates of traumatic stress were found in that 62% displayed symptoms consistent with posttraumatic stress disorder. Finally, logistic regression analyses revealed that traumatic stress, but not trauma exposure, was related to program completion. Findings suggest that treatment providers need to assess trauma histories and traumatic stress symptoms.