ABSTRACT Alzheimer’s Disease and related dementias (ADRD) disproportionately affect Black Americans compared to White Americans. Structural racism – the totality of ways by which society fosters racial discrimination and White supremacy through mutually reinforcing, inequitable systems in housing, education, employment, health care, criminal justice and other domains – may drive the constellation of social risk factors and comorbidities that increase the risk of ADRD. The mechanisms and pathways by which structural racism contributes to ADRD in Black Americans are as yet largely unexplored. We propose to assess the influence of structural racism on incidence of ADRD in a high-risk group of Americans, Black women. Our study will be based on participants and data from a 26-year follow-up study of 59,000 Black women from across the U.S., the Black Women’s Health Study (BWHS). We will develop a measure of structural racism that is more comprehensive than most currently in use and test characteristics of this measure against those of several published measures, at the county and state level. Our new measure will use data on unemployment, poverty, level of education, and incarceration; the data needed for its development will be obtained by linking participants’ geocoded addresses from 1995-2021 to appropriate public data sources. We will identify incident cases of ADRD through an already developed and tested method of linkage of BWHS participants aged 65 and older to Medicare data for the years 2008-2022; this will yield an estimated 1,500 incident cases of ADRD in 15,000 to 16,000 BWHS participants. Since enrollment in the BWHS in 1995, the participants have provided information on a large number of health and other factors, which include potential risk factors (e.g., hypertension, diabetes, low level of education) and protective factors (e.g., exercise, social support) for ADRD. The study has collected information at three different times on perceived experiences of interpersonal racism, and these reported experiences have been associated with increased risk of adverse health outcomes (e.g., weight gain) in the BWHS, as expected. Thus, it will be possible to assess the effects of structural racism alone on incidence of ADRD as well as the combined effects of structural and interpersonal racism. We will also study moderation or mediation of effects by a large number of other factors on the association of structural racism with incidence of ADRD. Since data have been collected over a period of 26 years in geographic areas across the U.S., it will be possible to assess effects of structural racism on ADRD incidence over time and place at the county and state level. Thus, the proposed study will provide new and important information on structural racism and ADRD in Black women.