 Our preliminary studies have shown that structured treatment interruption of highly active antiretroviral therapy HAART may boost patients immune responses to HIV-1. In this study, we will test the hypothesis that repeated structured treatment interruptions will increase HIV-1 immunity and result in better control of viral replication than in controls. We will test this hypothesis by determining time to viral rebound after withdrawal of antiretroviral therapy in a randomized, non-blinded study of a well-characterized subject population from a single center. Patients in this study will be randomized to either treatment interruption or control groups. Patients will be monitored for adherence to therapy and changes in immune status following HAART interruption. CD4 percentage, CD 4 and CD8 mediated anti-HIV-1 responses, cell surface T-cell antigen expression, and thymic function will be assessed. 