The Scientific Administrative Core (SAC), will be led by the Pediatric HIV/AIDS Cohort Study (PHACS) Principal Investigators (PIs), Drs. George R. Seage III and Ellen Chadwick and will be responsible for managing, coordinating, and supervising all program project grant activities, including assembling and maintaining the PHACS Scientific Leadership Committee (SLC) and all of its working groups, subcommittees, establishing collaborations with other research networks, and monitoring progress with respect to milestones, implementation of the overall Project Management Plan, and the proposed timelines. The staffing for the SAC will be based at the Harvard T.H. Chan School of Public Health (HSPH), as will the staffing of the Data Resources Core (DRC), in order to facilitate tight coordination and communication between the SAC and the DRC. The organizational and leadership structure of the SAC is designed to maximize efficiency in the implementation of the scientific agenda, ensuring excellence in the science and accountability in the conduct of the clinical research. Specifically, there are the following nine Aims of the SAC: 1. Manage, coordinate, and supervise all program project grant/research activities; 2. Outreach and establish collaborations with other networks; 3. Implement overall Project Management Plan and timelines and monitor progress; 4. Develop and maintain PHACS bylaws and policies and mitigate conflicts of interest; 5. Conduct an annual competition and selection of the PHACS Early Career Investigator Award; 6. Develop plans to mentor new and early stage investigators to develop independent research careers; 7. Recruit and support the activities of the PHACS External Advisory Committee (EC); 8. Maintain discretionary funds to support the focused Emerging Research Pilots (ERPs); 9. Hold an annual group meeting and annual leadership retreat to review accomplishments and plan the project agenda. The SAC will be based at HSPH under the administrative leadership of the PHACS Program Director, Liz Salomon, EdM. The PIs and the staff of the PHACS Core leadership (SAC, DRC and Health Education and Community and Epidemiological and Statistical Methods Cores) and the PIs of the PHACS Westat Inc. (Westat) subcontract, Julie Davidson, and the Frontier Science and Technology Research Foundation (FSTRF) subcontract, Sue Siminski, will meet weekly to facilitate coordination between the Cores and Research Projects.