BACKGROUND: Prior studies evaluating racial/ethnic differences in responses to antiretroviral therapy (ART) among HIV-infected patients have not adequately accounted for many potential confounders, and few have included Hispanic patients. OBJECTIVE: To identify racial/ethnic differences in ART adherence, and risk of AIDS and death after ART initiation for HIV patients with similar access to care. DESIGN: Retrospective cohort study. PARTICIPANTS: 4,686 HIV-infected patients (66% White, 20% Black, and 14% Hispanic) initiating ART and who were enrolled in an integrated healthcare system. MEASUREMENTS: Main outcomes evaluated were ART adherence, new AIDS clinical events, and all-cause mortality. The potential confounding effects of demographics, socioeconomic status, ART parameters, HIV disease stage, and other clinical parameters were considered in multivariable models. RESULTS: Adjusted mean adherence levels were higher among White (70.1%; ref) compared with Black (64.2%; P < 0.001) and Hispanic patients (65.2%; P < 0.001). Adjusted hazard ratios (HR) for the risk of new AIDS events (White patients as reference) were 1.3 (P = 0.09) for Black and 0.9 (P = 0.64) for Hispanic patients. The adjusted HR for AIDS comparing Hispanic to Black patients was 0.7 (P = 0.11). Hispanic patients had fewer deaths compared with other racial/ethnic groups, particularly cancer and cardiovascular-related. However, adjusted HRs for death were 1.2 (P = 0.37) and 0.9 (P = 0.62) for Black and Hispanic patients, respectively, compared with White patients and 0.9 (P = 0.63) for Hispanic compared with Black patients. Adjustment for adherence did not change inferences for AIDS or death. CONCLUSIONS: In the setting of similar access to care, we did not observe a disparity for the risk of clinical events for racial/ethnic minorities, despite lower ART adherence.