PROJECT SUMMARY/ABSTRACT Among the 12,000 deceased organ donors yearly in the US, there are racial disparities that have persisted over decades, with the Black population most recently donating at 69% of the White population. Relatively lower organ donation rates among racial minorities not only contribute to the organ shortage but also contribute to racial disparities in waitlisted candidate’s access to transplantation, with some racial minorities having longer wait times owing to difficult matching. Historically, efforts to address racial disparities in deceased organ donation have examined inpatient medical facility deaths, using inpatient death counts to estimate the potential organ donor pool, to benchmark successful organ recovery, and to target interventions. While only individuals who die in an inpatient medical facility can have their organs recovered for transplantation, the focus on this highly selected population is limiting. Structural racism, a determinant of racial disparities in health, affects healthcare resource availability, with Black individuals being 40% less likely than White individuals to have a usual source of healthcare in racially segregated neighborhoods. To date, healthcare resource availability has not been examined as a potential mediator of racial and geographic disparities in deceased organ donation. To better understand the impact of structural racism on deceased donor rates, we will perform novel linkages with three nationally representative datasets (Scientific Registry of Transplant Recipients, CDC WONDER, and National Health and Nutrition Examination Survey) to study the following aims: (1) To examine county-level risk factors for inpatient and outpatient death under medical conditions consistent with organ donation; (2) To examine the relationship between structural racism and the potential organ donor rate; and (3) To examine whether healthcare access mediates the relationship between structural racism and the potential organ donor rate. We hypothesize that structural racism affects inpatient facility death distribution, and subsequent organ donation rates, through its differential effects on healthcare access according to race and across geographies. If the proposed aims are achieved, we will directly inform national healthcare access and organ allocation policy, and population-level structural interventions to eliminate racial disparities in transplantation.