Abstract Introductory sentences indicating the purposes of the study: Using a modified version of Boot Camp Translation (BCT), a validated community participatory approach, we co-created locally relevant and culturally appropriate human papillomavirus (HPV) vaccination materials and messages for parents and caregivers of HPV vaccine-eligible children in Washington state. Brief description of pertinent experimental procedures: The HPV vaccine, recommended for children starting at age 9, reduces the risk of HPV infection and HPV-related cancers. However, HPV vaccine rates are significantly lower in rural regions compared to urban areas. In partnership with Kaiser Permanente Center for Health Research, the Huntsman Cancer Institute, and Sea Mar Community Health Centers, a large federally qualified health center in Washington state, we used a modified BCT approach to elicit input from parents and caregivers of HPV-vaccine eligible children to develop materials and messages that motivate parents to vaccinate their children. Eligible participants were parents or caregivers of children between the ages of 9-15 who had at least one vaccination, spoke English or Spanish, and were able to participate in the entire BCT process. Two BCT sessions were conducted (one in English and one in Spanish), both consisting of three meetings over a four-month period. The sessions included a five-hour in-person meeting in Aberdeen, Washington (English) and Bellingham, Washington (Spanish), and two one-hour follow-up virtual calls for each language. The in-person meetings included HPV vaccine education by Sea Mar providers and an expert in HPV research, discussions on HPV knowledge, perceptions, and barriers to vaccination, and small group discussions to generate HPV messages and materials. The follow-up calls gathered feedback on drafted materials and messages. Summary of the new unpublished data: Eight parents or caregivers participated in the English session and nine participated in the Spanish session. Key themes identified to incorporate in messages and materials included: stressing the benefits of vaccination, highlighting research on the vaccine’s safety and efficacy, including statistics and images of both girls and boys, reporting local statistics, spelling out HPV in materials, and emphasizing the words “prevent” and “protection” from cancers/infections later in a child’s life. The preferred materials and dissemination methods included: fact sheets and brochures (available in the clinic, mailed home, or in school nurses’ offices), posters (displayed in the clinic lobby and exam rooms), and animated videos (played on the clinic lobby TV and texted to parents’ phones). Participants also requested live phone calls from Sea Mar to discuss the importance of the vaccine and assist with vaccine scheduling. Final materials will be showcased.Statement of conclusions: We used a modified BCT approach to incorporate participant feedback to develop HPV vaccine messages and materials and identified preferred dissemination channels for rural communities in Washington state. Citation Format: Priyanka Gautom, Jamie H. Thompson, Jennifer S. Rivelli, Ludy Villegas, Anna C. Edelmann, Katherine Vaughn, Becca Slagle, Stephen Gubler, Kaila Christini, Amanda F. Petrik, Gloria D. Coronado, Deanna Kepka. Tailoring human papillomavirus (HPV) vaccine outreach for rural and Hispanic communities in Washington state: A modified Boot Camp Translation approach [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B078.