1. Emeritus Professor of Medical Demography, Faculty of Epidemiology and Population Health; London School of Hygiene and Tropical Medicine; London WC1E 7HT United Kingdom
2. Senior Adviser for Research and Evaluation, United States Agency for International Development (USAID), Office of Population and Reproductive Health, Washington, DC.
3. Director of the Center for Research and Evaluation in Reproductive Health, Harvard School of Public Health, Boston, MA.