Hematologic abnormalities remain an important feature of HIV infection, and they often limit the therapy of this disorder. This is currently a field of intense research, and some progress has already been made. The current development of newer, less myelosuppressive therapies for HIV infection is encouraging. In addition, as more is learned about the biochemistry, molecular biology, and pathophysiology of HIV and its effects upon its host, more effective, HIV-specific, and less toxic therapies may be developed. Finally, the use of various cytokines to ameliorate toxicities and possibly stimulate the functioning of myeloid cells is a promising area of research and should be pursued further. However, in spite of these efforts, much more needs to be done. In particular, therapy of HIV-associated lymphoma, which is likely to be increasingly observed as AIDS patients live longer, is often entirely unsatisfactory, in part because patients cannot tolerate the hematologic toxicity of the regimens employed. As in the general field of oncology, hematologic toxicities in AIDS remains a major limitation of therapy, and advances in this area have the potential to markedly improve both survival and quality of life.