Recent adult clinical trials involving combination HAART, including a protease inhibitor (PI), have demonstrated improvements in somatic immune system functioning. [AS PER AMENDMENT 2/27/01: More recently, similar success has been demonstrated with a PI-sparing regimen, zidovudine, lamivudine, and efavirenz.] Not all individuals, however, experience the same level of immune reconstitution, and oftentimes any improvement is short-lived. Adolescent patients may have a greater potential for immune restoration because of residual thymic tissue and therefore may experience greater long-term virus-free states as compared to adult patients. This study examines the duration of virologic efficacy HAART has on the adolescent HIV-positive population.