ACTG 219 is a longitudinal study of infants, children, and adolescents who have participated in perinatal and pediatric AIDS Clinical Trial Group (ACTG) clinical treatment trials in order to monitor long term survival and quality of life. ACTG clinical trials evaluate short term efficacy, safety and toxicity, however long terms outcomes and benefits of treatments, particularly on growth and development, cannot be adequately assessed during the time frame of a clinical trial. Children enrolled in this study will be followed from enrollment until 21 years of age. Study evaluations for ACTG 219 include assessments of growth and development, laboratory parameters and quality of life. The schedule of evaluations is determined by the HIV-infection status and age of the child.