Irene H. Yen, PhD, MPH, is an Associate Professor in the Division of General Internal Medicine, University of California, San Francisco (UCSF). Dr. Yen is affiliated faculty with the UCSF/UC Berkeley Robert Wood Johnson Health and Society Fellowship Program and the UCSF Center for Obesity Assessment Study and Treatment. Dr. Yen is Research Director for the Department of Medicine for Alameda Health System / Highland Hospital. Dr. Yen is a social epidemiologist with research expertise in survey design and development and qualitative research methods. Her research focuses on the social determinants of health, with emphases on how neighborhood environment influences health behaviors and health status and the intersections of race/ethnicity and social class. She has led a variety of research projects that investigate neighborhood environment and health. Dr. Yen is a member of the National Research Advisory Committee for the Association of Asian Pacific Islander Community Health Organizations and a commissioner for the City of Oakland Mayor’s Commission on Aging.