Ronald C. Kessler, Ph.D., is the McNeil Family Professor of Health Care Policy at Harvard Medical School. Dr Kessler's research deals with the social determinants of mental health and illness as studied from an epidemiological perspective. He is the author of over 700 publications and the recipient of many awards, including the Senior Scientist and MERIT awards from the National Institute of Mental Health. He has been rated as the most widely cited researcher in the world in the field of psychiatry for many years and is a member of the National Academy of Medicine and the National Academy of Sciences.