Dr. Jessica Barrington-Trimis is an epidemiologist and Associate Professor of Population and Public Health Sciences at the University of Southern California. She directs the USC Epidemiology of Substance Use Research Group and is a faculty member in the USC Institute for Addiction Science and the USC Norris Comprehensive Cancer Center. Dr. Barrington-Trimis' research focuses on investigation of the rapidly changing nicotine and cannabis landscape. Her work aims to identify intra-individual psychological, behavioral, and social processes associated with both nicotine and cannabis use in adolescence and early adulthood, and to elucidate the behavioral consequences (e.g., transition to more harmful patterns of substance use) and physiological consequences (e.g., dependence) of varying patterns of nicotine and cannabis use in adolescence, with the goal of informing regulatory efforts to protect adolescents and young adults.