Project Phidisa is a research collaboration between the South African Medical Health Services (SAMHS), the South African National Defence Force (SANDF), the US Department of Health and Human Services, National Institutes of Health (NIH), National Institute of Allergy and Infectious Diseases (NIAID), and the US Department of Defense (US DoD). The project aims to establish important biomedical and public health research capacity within the SANDF and a network of its clinics, sick bays and hospitals that can be used to address health issues of critical importance for military force-preparedness and to advance the global understanding of infectious disease. Strategic priorities of the program include: 1. Answering research questions relevant to South Africa on clinical management of HIV and other infectious diseases in the military, and 2. Building capacity within the SAMHS so that it can conduct research on other diseases of critical importance to military force populations.