This interagency agreement has the following scope: Clinical research on HIV and AIDS associated complications and co-infections with emphasis on optimizing therapeutic approaches to the treatment of HIV and related co-infections an co-morbidities in resource poor developing countries, including phase I-4 therapeutic clinical trials Clinical research on HIV prevention strategies ranging from novel pre-exposure prevention modalities such as Prevention of Mother to Child Transmission (PMTCT) and between discordant couples, treatment of sexually transmitted diseases, post exposure prophylaxis, and microbicides