Given the high prevalence of comorbid substance use and posttraumatic stress disorders (SUD-PTSD), how to best treat these patients is a pressing concern for SUD providers. PTSD treatment may play an important role in patients' recovery. One hundred male SUD-PTSD patients who attended SUD treatment completed 1-. 2-, and 5-year follow-ups. Outpatient treatment information was gathered from Veterans Affairs databases. PTSD treatment and 12-Step group attendance in the 1st year predicted 5-year SUD remission. Patients who received PTSD treatment in the first 3 months following discharge and those who received treatment for a longer duration in Year 1 were more likely to be remitted in Year 5. The receipt of PTSD-focused treatment immediately after SUD treatment may enhance long-term remission.