1 Professor of Public Health Sociology, Head of Department of Public Health, Environments and Society, London School of Hygiene and Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK. Electronic address: chris.bonell@lshtm.ac.uk.
2 Senior Lecturer in Social Sciences and Health, DECIPHer, School of Social Sciences, Cardiff University, 1-3 Museum Place, Cardiff CF10 3BD, UK. Electronic address: melendez-torresg@cardiff.ac.uk.
3 Associate Professor in Social and Environmental Innovation, School of Environment, Resources and Sustainability, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. Electronic address: squilley@uwaterloo.ca.