One of the most unusual manifestations of the acquired immunodeficiency syndrome is the cutaneous tumor, Kaposi's sarcoma. This rare and indolent tumor was once thought of as an interesting curiosity in Europe and Africa prior to the recognition of AIDS. Currently, however, this tumor accounts for approximately one quarter of all cases of AIDS recognized in the United States, and while not the proximate cause of death in most cases, Kaposi's sarcoma may cause severe physical and psychological morbidity in many patients. Treatment approaches must incorporate an understanding of the severe immunologic impairment in these individuals as well as their relatively poor tolerance to the myelosuppressive effects of many therapeutic agents. Treatment for Kaposi's sarcoma includes chemotherapy and radiation therapy, and more recently antiretroviral agents and immunomodulators in patients with indolent disease. Prophylactic treatment for Pneumocystis carinii pneumonia as well as nutritional and psychological support, and pain control are also important aspects of the care of these patients. This review will focus on the pathogenesis and natural history of Kaposi's sarcoma and review the treatment approaches and limitations of therapy for this tumor.