Three hematopoietic stimulants have been used in patients with HIV infection and a variety of AIDS-related complications. Both G-CSF and GM-CSF have demonstrated the ability to correct leukopenia related to HIV infection and ameliorate the drug-related myelosuppressive effects of zidovudine, trimethoprim/sulfamethoxazole, ganciclovir, and, in the case of GM-CSF, alpha-interferon, and cancer chemotherapies. Erythropoietin has been successfully used to ameliorate the anemia associated with HIV infection and zidovudine therapy. Treatment with these hematopoietic stimulants is very well tolerated with minimal toxicity. Of the granulocyte stimulants, G-CSF appears to induce fewer side effects than GM-CSF in trials conducted to date. Future trials demonstrating that the amelioration of hematopoietic suppression by the colony-stimulating factors results in increased clinical response rates and improved survival are necessary to fully assess the value of this approach in the care of HIV-infected patients.