Medication adherence is a critical issue for HIV infected children and adolescents because of drug resistance and the increased complexity of treatment regimens. Children and adolescents with HIV face depression, anxiety, denial, and rebellion that may interfere with their motivation to take medication. Depression and self-perceived social support have been found to predict regimen adherence in adults with HIV. Children with other chronic diseases are less likely to adhere to their medication regimens if they also have behavioral or emotional problems; assessing emotional and behavioral function in children and adolescents with HIV may help in predicting adherence and explaining adherence failure. This study will correlate cognitive, behavioral, and psychosocial functioning with measures of virologic suppression and immunological status, and it will compare self-report and pill count measures of adherence in a randomly selected subset of perinatally infected HIV participants of PACTG 219C.