I am a social anthropologist by training. I have a PhD in that subject from the University of Cambridge. Before joining the London School of Hygiene and Tropical Medicine in April 2014 I was Professor of International Development at the University of East Anglia. I worked for the Department for International Development for 13 years, prior to moving to the University of East Anglia in 2000. I am interested in the social aspects of health, with particular interest in HIV, tuberculosis and non-communicable conditions. I have worked in a number of different countries over the last 40 years. I have been actively engaged in research on HIV since the late 1980s, including four years with Medical Research Council in Uganda 1989-1993 when I was responsible for setting up social science research in the Unit, the Programme I returned to Uganda to head in 2008 up until March 2022. 

Since 2014, I have been supporting social science and ethics research and researchers at the Africa Health Research Institute (formerly Africa Centre) in KwaZulu-Natal, South Africa. I am currently a member of faculty covering Social Science and Research Ethics.

December 2016-May 2019 I was a research director for STRIVE (http://strive.lshtm.ac.uk/).

I am currently the head of the Department of Global Health and Development.