AIM: We examined the association of substance abuse treatment with uptake, adherence and virological response to highly active antiretroviral therapy (HAART) among HIV-infected people with a history of alcohol problems. DESIGN: Prospective cohort study. METHODS: A standardized questionnaire was administered to 349 HIV-infected participants with a history of alcohol problems regarding demographics, substance use, use of substance abuse treatment and uptake of and adherence to HAART. These subjects were followed every 6 months for up to seven occasions. We defined substance abuse treatment services as any of the following in the past 6 months: 12 weeks in a half-way house or residential facility; 12 visits to a substance abuse counselor or mental health professional; or participation in any methadone maintenance program. Our outcome variables were uptake of antiretroviral therapy, 30-day self-reported adherence and HIV viral load suppression. FINDINGS: At baseline, 59% (205/349) of subjects were receiving HAART. Engagement in substance abuse treatment was independently associated with receiving antiretroviral therapy (adjusted OR; 95% CI: 1.70; 1.03-2.83). Substance abuse treatment was not associated with 30-day adherence or HIV viral load suppression. More depressive symptoms (0.48; 0.32-0.78) and use of drugs or alcohol in the previous 30 days (0.17; 0.11-0.28) were associated with worse 30-day adherence. HIV viral load suppression was positively associated with higher doses of antiretroviral medication (1.29; 1.15-1.45) and older age (1.04; 1.00-1.07) and negatively associated with use of drugs or alcohol in the previous 30 days (0.51; 0.33-0.78). CONCLUSION: Substance abuse treatment was associated with receipt of HAART; however, it was not associated with adherence or HIV viral load suppression. Substance abuse treatment programs may provide an opportunity for HIV-infected people with alcohol or drug problems to openly address issues of HIV care including enhancing adherence to HAART.