Much progress has been made in implementing potent antiretroviral therapy that is able to maximally suppress viral replication. However, these drug combinations do not result in viral eradication and, for many patients, virologic and immunologic control cannot be maintained. Even among patients with apparent virologic control, a "ceiling effect" seems to exist with failure of CD4 cell counts to rise on average more than 100 to 150 cells/mm^3, at least during the first 2 years of therapy. The incomplete recovery of immune function after initiation of therapy remains an obstacle in the management of HIV. Preservation of immune function by direct expansion of CD4 lymphocytes with rIL-2 could represent a significant additional treatment strategy. It also has been speculated recently that rIL-2 in combination with potent antiretroviral therapy may be a useful approach for purging HIV from the latently infected CD4 cells. It is hoped that intervention with rIL-2 therapy in combination with antiretroviral therapy at an early stage of HIV infection can prevent CD4 T-cell depletion and result in fewer AIDS-defining illnesses than with antiretroviral therapy alone.