Since January 1990, human immunodeficiency virus (HIV)-infected patients attending two sexually transmitted disease clinics in Baltimore, Md, have been offered T-lymphocyte subset evaluations. From January through September, CD4+ lymphocyte concentrations were measured in 223 newly diagnosed HIV-infected patients; 50% had fewer than 500 CD4+ T cells and 12% had fewer than 200 CD4+ T cells per cubic millimeter. Most patients were asymptomatic, and, even among patients with fewer than 200 CD4+ T cells, 54% had no symptoms or signs suggestive of advanced HIV infection. Homosexually active men had significantly lower mean CD4+ lymphocyte concentrations than intravenous drug users. Given the substantial numbers of patients with CD4+ concentrations that qualified them for zidovudine therapy, we also assessed their mechanisms of paying for health care. Only 24% of HIV-infected patients had private insurance. Seventy-two percent of patients with fewer than 200 CD4+ T cells either had no insurance or relied on public assistance for health care. Thus, although 50% of asymptomatic individuals identified by routine voluntary HIV screening in an inner-city sexually transmitted disease clinic may benefit from therapy for their disease, 75% of those qualifying for presently recommended therapy either depend on publicly funded health care or have no means of payment for care. © 1991, American Medical Association. All rights reserved.