Jaime E. Hart is an Associate Professor of Medicine at the Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School and in the Department of Environmental Health at the Harvard TH Chan School of Public Health. She is an environmental epidemiologist and studies the associations between multiple environmental exposures, often referred to as the external exposome, and risk of chronic disease and health behaviors. Most of her work is based in long running prospective cohorts at CDNM, including the Nurses’ Health Studies, where she serves as Director of Geographic and Contextual Measures. She also helps to run the Growing Up Today Study in her role as Scientific Director.