Professional Psychology: Research and Practice Vol. 48, Iss. 6,  (Dec 2017): 490-498. Comorbid diagnoses of substance use disorders (SUDs) and posttraumatic stress disorder (PTSD) are quite high among individuals seeking residential SUD treatment, and are associated with both poor treatment engagement and outcomes. The current study examines the impact of trauma type (e.g., Criterion A/non-Criterion A; substance-related/non-substance-related) on subjective distress and concurrent PTSD and SUD symptom severity in a sample of 50 trauma survivors seeking residential treatment for substance use.