A retrospective, longitudinal analysis of case management and medical charts was used to evaluate utilization of support group, mental health, and substance abuse treatment services among HIV-positive women in New York City. Analyses of 4134 case management and supportive service transactions revealed that 70% utilized support groups over the two-year study period. In contrast, only 35% utilized mental health services (therapy) and of those identified as using substances, only 48% utilized substance abuse treatment services. Considering the high prevalence of mental illness (63%, n=29) and substance use (54%, n=25) in the sample, the low utilization rates highlight unmet needs for service. Significant differences were found in utilization of mental health and substance abuse treatment services, with those who received services at a medical model agency (integrated care) being more likely to receive both types of treatment. In contrast, participants attending support groups in non-medical model agencies (77.8%, n=7) were significantly more likely to be retained in group (i.e., attend 11 or more sessions) than those at medical model agencies (39.1%, n=9). Based on the higher utilization rates of support groups among seropositive women, perhaps these groups could be a vehicle for establishing rapport between mental health professionals and group members to bridge the utilization gap and reduce the stigma associated with therapy and substance abuse treatment services. These findings both taut the success and highlight weaknesses regarding accessing mental health and substance abuse care, and support group retention. Sharing of information regarding recruitment and retention efforts between agencies of different modalities would be beneficial and also could identify service niches that capitalize on their subsequent strengths.