The purpose of this study is to determine what combinations of anti-HIV drugs work best in patients treated over several years. The study will also assess the occurrence of side effects and opportunistic infections in patients with low viral loads compared to those with higher viral loads.

A compilation of outcomes of various antiretroviral therapies would be beneficial when evaluating which strategies are most effective in long-term treatment of HIV-1. Using data from present and recently completed studies, this study will collect information on therapies and their control of HIV infection and maintenance of durable suppression of HIV-1 replication.

No treatment is provided by this study, but patients will continue to receive highly active antiretroviral therapy (HAART) from other studies in which they are coenrolled. Blood and urine collection will occur at study entry and periodically throughout the study. Women may undergo pelvic exams and Pap smears. Portions of blood samples will be stored to evaluate genotypic/phenotypic susceptibility testing. Medical histories, physical exams, and questionnaires will be completed periodically.

Inclusion Criteria

• HIV-1 infected
• Enrolled in an AIDS Clinical Trial Group (ACTG) parent study and has enrolled in this study on or before the Week 16 visit of the parent study, including the visit window of the parent study. More information on this criterion can be found in the protocol.
• Willing to provide consent for the release and use of clinical data from the parent study
• Life expectancy of at least 24 weeks
• Parent or guardian willing to provide informed consent, if applicable

Exclusion Criteria

• Active alcohol or drug abuse that may interfere with the study

Participants in this study will be HIV-infected men and women who are enrolled in an ACTG parent study and are receiving HAART.