To determine why HIV-infected persons do not access needed services, we interviewed clients of Ryan White CARE-funded agencies in San Francisco, San Mateo and Marin Counties. From July to September 1996, we interviewed 519 clients receiving services at 65 CARE-funded sites. Just over half the clients (54.5%) had at least one unmet service need in the previous four months; persons in an unstable living situation and those with lower perceived health status were significantly more likely to have an unmet need. For persons with unmet needs, agency barriers were most common (54.0%), followed by emotional issues (44.8%), lack of information (44.0%) and financial/practical barriers (19.4%). None of the client characteristics (sex, race/ethnicity, age, living situation, perceived health status and risk group) were consistently or significantly (p < 0.05) associated with specific barriers. We believe that the similarity between clients with and without unmet needs reflects the success of CARE in eliminating many barriers. However, the persistence of certain barriers and lack of sub-group-specific barriers suggests the need for individualized interventions to improve service delivery, publicize service availability and address the emotional barriers to accessing HIV-related care.