Sarah Bernays holds a joint position as an associate professor at the London School of Hygiene and Tropical Medicine and a senior lecturer at University of Sydney. She is a medical anthropologist, specialising in sexual and reproductive health in east and southern Africa. Adam Bourne is an associate professor of public health in the Australian Research Centre in Sex, Health and Society at La Trobe University, Melbourne, where he leads the LGBTIQ health and wellbeing research program. He has worked extensively in social and behavioural HIV prevention and care research among gay, bisexual and other men who have sex with men across Europe, Sub-Saharan Africa and South East Asia. Susan Kippax is an emeritus professor in the Social Policy Research Centre at UNSW Sydney and a Fellow of the Academy of the Social Sciences of Australia.  For many years she was the director of the National Centre in HIV Social Research.  She is former joint Editor-in-Chief of the Journal of the International AIDS Society and her most recent book (with Niamh Stephenson) is Socialising the Biomedical Turn in HIV Prevention (2016, Anthem). Peter Aggleton has worked internationally on the social aspects of HIV, sexuality, gender, health and rights for over 30 years. He is an emeritus professor at UNSW Sydney; a distinguished honorary professor at the Australian National University; and an honorary professor in the Centre for Gender and Global Health at UCL in London.  He is Editor-in-Chief of Culture, Health & Sexuality, Health Education Journal and Sex Education. Richard Parker is a professor emeritus in sociomedical sciences and anthropology at Columbia University and a senior visiting professor in the Institute for the Study of Collective Health at the Federal University of Rio de Janeiro, as well as the director of ABIA (the Associação Brasileira Interdiscplinar de AIDS) and Editor-in-Chief of Global Public Health. His research has focused on the social and cultural construction of gender and sexuality, the social aspects of HIV, and the politics of global health.