Mark Nelson is a consultant physician at the Chelsea and Westminster Hospital, London. He trained at Jesus College, Cambridge and Westminster Hospital Medical School, qualifying in 1986. Appointed Consultant Physician there in 1991, he presently leads patient and day case HIV care and is Professor of HIV Medicine at Imperial College Medical School and deputy senior tutor. He has built a large HIV practice with a special interest in patient care, co infection with hepatitis B and C, and the clinical utility of new antiretroviral agents. He has published over 500 papers on HIV and hepatitis. Professor Nelson has chaired the British HIV/AIDS Association (BHIVA) guidelines committee for opportunistic infections and for hepatitis C and sits on the Guidelines Committees for Treatment, Malignancy and HIV transmission. He was previously chair of the BHIVA hepatitis special interest group and chair of the BHIVA science and education committee. He is a trustee of several HIV-associated charities, including IAPAC. He devotes most of his charitable time now to establishing HIV treatment networks in Burma and Vietnam. He has been awarded a visiting professorship at the Aga Khan Hospital, Nairobi, Kenya and most recently the certificate of merit by the government of Vietnam.