The overall aim of the proposed staff exchange program is to establish a long lasting collaboration between South African and European research teams involved in HIV co-infection research. This effort ultimately should lead to new ways to improve the care/treatment for patients with HIV co-infections and to decrease the high mortality among persons with HIV infection in Africa.South Africa is the country with the largest number of HIV tuberculosis (TB) co-infected patients in the world. With this program we will explore new ways to diagnose and treat TB more rapidly and investigate why HIV co-infected patients still die despite increasing access to effective anti-retroviral HIV treatment. South Africa has also a huge burden of disease caused by Hepatitis B and Human papillomavirus infections. So far, HIV research in Africa has neglected to address non-TB HIV co-infection research questions. With this exchange program we will explore how to close this research gap.During the project we will: train early stage researchers in state-of-the-art field research, laboratory techniques, data collection and data analysis, build a network of researchers interested in HIV co-infection research, formulate and perform new collaborative research projects by intensifying research partnerships and networking activities.The consortium consists of very complementary partners (2 South African and 4 European) with a common interest in HIV co-infection research. The University of Cape Town is an extremely interesting partner because it is one of Africa's leading teaching and research institutions. The University of Limpopo offers many research opportunities because of its focus on rural Africa and on working with disadvantaged communities. Existing links between partners and research funds that are already available will facilitate the rapid start of the exchange program. The envisaged 4-year program will consist mainly of visits of early stage researchers (PhD students)