David Heymann is Head and Senior Fellow of the Centre on Global Health Security at Chatham House (Royal Institute of International Affairs, UK), Chairman of Public Health England, and a Professor of Infectious Disease Epidemiology at the London School of Hygiene and Tropical Medicine. Previously he was the World Health Organization's Assistant Director-General for Health Security and Environment, and Representative of the Director-General for Polio Eradication. From 1998 to 2003 he was Executive Director of the WHO Communicable Diseases Cluster, during which time he headed the global response to SARS, and prior to that was Director for the WHO Programme on Emerging and Other Communicable Diseases. Earlier experiences at WHO include chief of research activities in the WHO Global Programme on AIDS. Before joining WHO he worked for 13 years as a medical epidemiologist in sub-Saharan Africa, on assignment from the US Centers for Disease Control and Prevention (CDC), where he participated in the first and second outbreaks of Ebola hemorrhagic fever, and supported ministries of health in research aimed at better control of malaria, measles, tuberculosis and other infectious diseases. Prior to joining CDC he worked in India for two years as a medical epidemiologist in the WHO smallpox eradication programme. He is an elected fellow of the Institute of Medicine of the National Academies (US) and the Academy of Medical Sciences (UK), and has been awarded several public health awards that have provided funding for the establishment of an on-going mentorship programme at the International Association of Public Health Institutes (IANPHI). In 2009 he was appointed an honorary Commander of the Most Excellent Order of the British Empire (CBE) for service to global public health.