The rates of progression of human immunodeficiency virus (HIV) infection and survival have been reported to differ among sociodemographic groups. It is unclear whether these differences reflect biologic differences or differences in access to medical care. We measured disease progression and survival in a cohort of 1372 patients seropositive for HIV who were treated at a single urban center (median follow-up, 1.6 years). We calculated the rates of survival for the entire cohort and the rates of progression to the acquired immunodeficiency syndrome (AIDS) or death among the 740 patients who presented without AIDS. We used Cox proportional-hazards analysis to examine factors associated with progression to AIDS and death. Progression to AIDS or death was associated with a CD4 cell count of 201 to 350 per cubic millimeter (relative risk, 2.0; P < 0.001), the presence of symptoms at base line (relative risk, 2.0; P < 0.001), prior antiretroviral therapy (relative risk, 1.7; P = 0.003), and older age (relative risk per year of age, 1.02; P = 0.03). However, there was no relation between disease progression and sex, race, injection-drug use, income, level of education, or insurance status. In the entire cohort, a lower CD4 cell count, a diagnosis of AIDS, older age, and the receipt of antiretroviral therapy before enrollment were associated with an increased risk of death, whereas the use of prophylaxis against pneumocystis pneumonia, zidovudine use after enrollment, and having a job at base line were associated with lower risks of death. There was no significant difference in survival between men and women, blacks and whites, injection-drug users and those who did not use drugs, or patients whose median annual incomes were $5,000 or less and those whose incomes were more than $5,000. Among patients with HIV infection who received medical care from a single urban center, there were no differences in disease progression or survival associated with sex, race, injection-drug use, or socioeconomic status. Differences found in other studies may reflect differences in the use of medical care.