Data Core: Project Summary The Massachusetts Institute for Equity-Focused Learning Health System Science (MIELHSS) brings together an alliance of FQHCs, Safety Net Hospitals, Community Clinics, Patients, PCORnet sites, and leading academic health systems who share a common purpose to accelerate research and train the future workforce to advance learning health system science, address disparities, and improve health outcomes for the U.S. The Research Data Core is central to the work of MIELHSS scholars, providing mentorship and support of their data needs and focusing on AHRQ/PCORI priorities. The Research Core strives to further expand the impact of the Institute on AHRQ/PCORI priorities around health equity by developing common data standards, shared practices, and an infrastructure regarding equity data measures and social drivers of health across the MIELHSS Network. Specifically, the goals of the Research Data Core are: 1) develop a shared federated data set of equity-focused data measures and Social Drivers of Health (SDOH), 2) support cross-organizational research by establishing mechanisms to compare data through distributed data analysis using a federated approach and 3) work with the Administrative Core, Executive Committee, External Advisory Committee, mentors, and scholars to catalogue and actively disseminate scientific information from MIELHSS across MIELHSS organizations, New England, and the country to advance health equity.