Background: Chronic non-cancer pain and substance use disorders frequently co-occur in VA primary care and addictions treatment settings. The treatment for pain is complicated in veterans with a history of alcohol or drug misuse because of a potential for abuse and diversion of many prescription pain medications. Thus, treatment providers are left without successful and empirically-supported methods for treating the large number of patients with chronic pain who also have past or current substance use disorders. One potential strategy is to use cognitive-behavioral treatment (CBT) interventions to manage pain and decrease substance use abuse/misuse. Psychosocial interventions such as CBT have demonstrated efficacy for reducing pain and improving functioning in persons with a broad spectrum of pain-related problems. However, this form of treatment has not been explicitly tested in patients with co-occurring substance use disorders. Determining the effectiveness of a psychosocial intervention targeting both pain and substance use disorders would greatly increase the available treatment options for veterans with these conditions.