PROJECT SUMMARY Population health statistics paint a sobering portrait of U.S. women’s health, particularly among women from NIH-designated health disparity or understudied, underrepresented, and underreported (U3) populations. The broad scope and unequal patterning of U.S. women’s health disadvantage underscores the need for interdisciplinary research into related trends and trajectories, causes, and consequences. In particular, as recognized in reports by the NIH and other scientific bodies, population science on women’s health must consider a wide range of social and structural determinants as well as the contributions of healthcare, medicine, and biology, requiring interdisciplinary training and collaboration. To respond to this need, the Population Studies and Training Center (PSTC) at Brown University requests supplemental funding to support the development of research on women’s health among women from U3 populations under its Population Dynamics Centers Research Infrastructure Program grant (P2CHD041020-23). This request is in response to the Notice of Special Interest (NOSI): Research on the Health of Women of Understudied, Underrepresented and Underreported (U3) Populations (NOT-OD-24-032). With this supplement, PSTC will establish the Initiative in Women’s Health Equity to bring together scholars from the social sciences, public health, and medicine at Brown with the overarching goal of building interdisciplinary teams with diverse expertise to advance population science in this area. Expanding the PSTC research portfolio to include research on women’s health that specifically focuses on women from NIH-designated health disparity or understudied, underrepresented, and underreported (U3) populations in biomedical research will enhance and expand science in PSTC’s Primary Research Areas of Migration and Urbanization; Children, Families, and Health; Reproductive Health and HIV/AIDS; Population, Development, and Environment; and Social Foundations of Health Disparities. Applying PSTC expertise on the social and structural contexts that produce inequality, and diminish health and well-being for marginalized populations, to research on women’s health, will contribute to ORWH efforts to build interdisciplinary research focused on the effect of sex and gender at the intersection of the social determinants of health and disease.