Robert H. Friis, PhD, earned his doctorate from Columbia University and completed a postdoctoral fellowship in social epidemiology at the Institute for Social Research, University of Michigan, Ann Arbor. He received his Bachelor of Arts degree in psychology from the University of California at Berkeley. He has had more than three decades of teaching and research experience in epidemiology. Formerly, he was Assistant Professor of Epidemiology at the Columbia University School of Public Health, Assistant Professor of Pediatrics and Community Health at Albert Einstein College of Medicine, and Assistant Professor of Health Science at Brooklyn College of the City University of New York. Subsequently, he was Director of the Field Epidemiology Unit at the Orange County (California) Public Health Department. Later he became a faculty member in the Department of Medicine, Department of Neurology, and the School of Social Ecology at the University of California, Irvine. Currently, he is Professor and Chair of the Health Science Department at California State University, Long Beach, where he has taught introductory epidemiology and biostatistics. He has been involved in numerous epidemiologic research projects and has drafted more than 50 professional and scientific articles. He is a member of the Society for Epidemiologic Research and the epidemiology section of the American Public Health Association. He is also Clinical Professor of Community and Environmental Medicine at the University of California, Irvine. See the author as the “Expert” in Epidemiology in a short video on “Video Jug.”