Samuel R. Friedman is a Research Professor and a faculty member at the Center for Opioid Epidemiology and Policy in the Department of Population Health at NYU Grossman School of Medicine. He is also the Senior Theoretician and Associate Director of the Infectious Disease Epidemiology and Theory Core at the Center for Drug Use and HIV Research (CDUHR). He obtained his doctorate from the University of Michigan School of Sociology and has received numerous awards for his research on people who use drugs and HIV/AIDS. Over the last thirty-five years, Dr. Friedman has significantly contributed to our understanding of harm reduction and of the epidemiology and prevention of HIV/AIDS and other infections among people who use drugs. His current research focuses on opioid users in rural Illinois and in New York City. His past and ongoing research has focused on the social epidemiology and social network aspects of drug use and infectious diseases.