Nagalingeswara Kumarasamy, MD is Chief and Director, Infectious Diseases Medical Centre, Voluntary Health Services Hospital, Chennai, Southern India. The clinic he directs provides medical care for more than 20,000 persons living with HIV and infectious diseases. He is Director and Site Leader, Chennai Antiviral Research and Treatment (CART) Clinical Research Site, US National Institutes of Health (NIH). It conducts multisite clinical trials of therapeutics (AIDS clinical treatment group – ACTG) and trials for the HIV prevention trials network (HPTN). He is a clinical investigator for on-going clinical research projects with the University of California (San Diego); Brown University (Providence); Harvard University, Boston, USA; and University of New South Wales/Kirby Institute, Sydney, Australia. A clinician with more than 20 years of research experience, Dr. Kumarasamy has published more than 350 manuscripts in peer-reviewed journals. Several landmark antiretroviral clinical trials he conducted have informed treatment guidelines and influenced antiretroviral scale-up programs in low- and middle-income countries. He is an expert panel member for the World Health Organization’s Committee on antiretroviral treatment guidelines and a clinical advisor for the Clinton Health Access Initiative. Currently, he is Regional Representative for Asia for ACTG/NIH. He has a particular interest in the long-term impact of antiretroviral therapy in resource-limited settings.