More than half of substance abusers entering addiction treatment report a history of physical or sexual abuse. It is unclear if such a history impacts treatment outcomes. This one-year follow-up study of 700 substance abusers sought to clarify the relationship between lifetime physical and/or sexual abuse and addiction treatment outcome to help address the specific needs of this population. To achieve this goal, baseline characteristics, no-show for treatment status, post-treatment clinical outcomes, and treatment history were studied for subjects with lifetime history of abuse (47.3%) versus without. Abused subjects, predominantly women, were significantly more impaired at baseline on clinical dimensions including family/social severity and psychiatric severity as measured by the Addiction Severity Index (ASI), and general level of functioning. The two groups endorsed different drugs as primary, with the abused group less frequently endorsing heroin and cocaine in favor of alcohol and polydrug use. Abused subjects reported more prior medical and psychiatric treatments. Abuse history was not a predictor of no-show for treatment. Over the 1-year follow-up, lifetime physical and/or sexual abuse was significantly associated with worse psychiatric status and more psychiatric hospitalizations and outpatient treatment despite receiving similar intensive addiction treatment.