Ronald C. Kessler is the McNeil Family Professor of Health Care Policy at Harvard Medical School. His research deals broadly with the social determinants of mental illness from an epidemiological perspective. He is the author of over 700 publications and the recipient of many awards for his research, including Senior Scientist and MERIT awards from NIMH. He has been rated as the most widely cited researcher in the world in psychiatry for the past two decades. He is a member of both the Institute of Medicine and National Academy of Sciences. Kessler is the Principal Investigator of the US National Comorbidity Survey, the first nationally representative survey of the prevalence and correlates of mental disorders in the U.S., and Co-Director of the World Health Organization’s World Mental Health Survey Initiative, a series of comparative community epidemiological surveys of the prevalence and correlates of mental disorders in 30 countries around the world. He is involved in evaluating a number of innovative programs for the prevention and treatment of mental illness in high-risk segments of the population. He is also the HMS PI of the STARRS-LS program of research on risk and protective factors for suicide among Army personnel, the AURORA study of adverse neuropsychiatric reactions to traumatic life events among patients presenting to emergency departments in the wake of such events, and the Appalachia Mind Health pragmatic trial of augmenting pharmacotherapy for major depression with remote internet-based CBT among low-income rural primary care patients in Kentucky and West Virginia. Much of his work in the latter studies involves his work in the Precision Treatment of Mental Disorders (PTMD) initiative developing and implementing precision treatment models to determine the right interventions for the right patients. Kessler earned his PhD in sociology from New York University, completed a postdoctoral fellowship in psychiatric epidemiology at the University of Wisconsin, and was on the faculty at the University of Michigan before taking his current position in 1995 at HMS.