The PHACS Data Resources Core (DRC) (Principal Investigator (PI): George R. Seage III, DSc, MPH) will provide overall program project management, house the merged database, and provide programming and analytical leadership for the Pediatric HIV/AIDS Cohort Study (PHACS) 2020 P01 Program Project. The DRC will continue to subcontract with PHACS clinical sites as well as Westat, Inc. (?Westat?) and Frontier Science and Technology Research Foundation (?FSTRF?) which will support monitoring of clinical sites and data management operations respectively. In PHACS 2020, the aims of the DRC will be to: 1. Develop and direct the overarching Project Management Plan for the PHACS 2020 Cores and Research Projects. 2. Execute and manage subcontracts for collaborating partners and clinical sites. 3. Provide support to the Single IRB (sIRB) process and regulatory and compliance management for clinical sites. 4. Utilize its relationship with and direct access to clinical sites and their personnel, including Clinical Investigators, Study Staff and Community Advisory Board (CAB) members, to efficiently and effectively implement all PHACS 2020 Research Projects and manage and monitor performance. 5. Serve as the centralized data and resource management entity for PHACS 2020. 6. Provide sample tracking, manage sample storage, and oversee laboratory data management. 7. Manage data storage and access. 8. Oversee and execute the sharing and transfer of PHACS samples and data as well as the receipt of data for collaborations. 9. Provide programming and analytical core services for integrated data analysis. 10. Serve as a shared resource to all PHACS 2020 Cores and Research Projects. The DRC will be based at the Harvard T.H. Chan School of Public Health (HSPH) under the day-to-day administrative leadership of the PHACS Program Director, Liz Salomon, EdM. The PIs and the staff of the PHACS Core leadership (DRC, Scientific Administrative Core, Health Education and Community Core, and Epidemiological and Statistical Methods Core) as well as the PIs of the PHACS FSTRF subcontract, Sue Siminski, MS, MBA and the Westat subcontract, Julie Davidson, MSN will meet weekly to facilitate coordination between the Cores in service to the Research Projects. Monthly meetings and regular communications will also occur between the DRC and PHACS Clinical Investigators, Study Staff and CABs.