Ethnic minority, female, and drug-using patients may be less likely to receive highly active antiretroviral therapy (HAART), despite its proven benefits. We reviewed the medical records of a consecutive population of 354 patients entering care in 1998 at the Thomas Street Clinic, an academically affiliated, public, HIV-specialty clinic in Houston, to determine the factors associated with not receiving HAART as recorded in pharmacy records. Ninety-two patients (26.0%) did not receive HAART during at least 6 months of follow-up. Patients who did not receive HAART were more likely to be women and to have missed more than two physician appointments and were less likely to have a CD4 count <200 cells/μL or a viral load ≥105 copies/mL. In multivariate logistic analysis, missed appointments (OR = 5.85, p < .0001), female sex (OR = 2.53, p = .001), and CD4 count ≥200 cells/μL (OR = 2.50, p = .001) were independent predictors of not receiving HAART. More than half the patients who never received HAART never returned to the clinic after their first appointment. Among patients new to care, women and those with poor appointment adherence were less likely to receive HAART. Efforts to improve clinic retention and further study of the barriers to HAART use in women are needed.