Abstract This poster demonstrates that advocacy support enhances diversity recruitment in the WISDOM Study (Women Informed to Screen Depending on Measures of Risk). Initially funded by a grant from the Patient-Centered Outcomes Research Institute, with advocates having a key role in design and planning, WISDOM is a 100,000 healthy women preference-tolerant, pragmatic study comparing annual to personalized risk-based breast screening. The novelty of WISDOM personalized screening is the integration of previously validated genetics and clinical risk factors (age, family history, breast biopsy results, ethnicity, mammographic density) into a single risk-assessment model that directs the starting age, timing, and frequency of screening. Importantly, the genetic component of risk is calibrated by race/ethnicity (Caucasian, Asian, African American, Hispanic), to provide each woman the most tailored personalized risk assessment. The goal of WISDOM is to determine if personalized screening, compared to annual screening, is as safe, less morbid, enables prevention, and is preferred by women. The study is registered on ClinicalTrials.gov, NCT02620852. The study's “preference-tolerant design” encourages women to be randomized but also allows self-assignment (this component was recommended by advocates) for those with a strong personal preference for either annual or risk-based screening. WISDOM study researchers aim to help all women make better-informed decisions by comparing the outcomes of women who have annual mammograms with those women who received mammograms on a schedule determined by their personal risk. Enrollment and consent take place entirely online at www.wisdomstudy.org, which serves as a patient portal where participants register, complete electronic consent, take health-related questionnaires and receive screening recommendations and genetic test results. Currently the clinical sites and infrastructure associated with this study are part of the Athena Breast Health Network (Athena), a unique collaboration among the five University of California (UC) medical/cancer centers (UCSF, UC Davis, UCLA, UC Irvine, and UCSD) and the Sanford Health System (based in Sioux Falls, SD). Athena has fostered partnerships with advocates since its inception in 2009 and formed the Consumer and Community Advisory Committee (CCAC). The CCAC comprises patient advocate representatives from each Athena site and community members with expertise in public heath, breast health, and under-represented populations. In addition to participation at twice-yearly WISDOM Retreats, advocates participate on regular WebEx WISDOM Study calls with committee updates on advocacy involvement, marketing and outreach materials, recruitment, bioethics, protocol and adherence. Each advocate's skills and background inform all aspects of the study as we focus on addressing recruitment strategies for expanding and encouraging enrollment in traditionally under-represented populations including, but not limited to, racial/ethnic, underserved, older women, and women with little or no access to the internet. Advocates, partnering with study staff, are championing efforts to further WISDOM diversity outreach by identifying key community champions in women's organizations, local nonprofits and faith-based organizations; identifying people who do community-based research and have established community relations; working on strategies on what we can offer to the community such as presentations events and in-person discussions; and, finally, helping to bridge technology gaps and access. As of July 2018, the WISDOM study is open to all eligible women in California, North Dakota, South Dakota, Minnesota and Iowa. To date, 23,329 eligible women have registered and 14,393 women have consented to participate in the trial. The median age is 56 years, 82% Caucasian, 1% African-American, and 6% Asian, and 9% self-reporting as Hispanic. WISDOM Study data collected so far do not reflect the diversity of our potential participant population. We are partnering with health insurers and self-insured companies and expanding to other states with enrollment continuing past 2019. With the engagement of patient advocates, expanding diversity recruitment will help fill gaps in scientific knowledge, resulting in personalized breast cancer screening recommendations for all women. Citation Format: Susie Brain. [Advocate Abstract] Advocating for diversity in the WISDOM Breast Cancer Screening Study [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr B078.