PROJECT SUMMARY Chronic disease causes the most death and disability in the United States (US), and American Indian/Alaska Native people (ANAIs) are more likely than people of all other races to die of heart disease, diabetes, chronic lower respiratory disease, cirrhosis, stroke, pneumonia, kidney disease, and hypertension. Among ANAIs age 55 and older, 90% have at least one chronic condition, compared with 78% of their US peers. As the older ANAI population rapidly increases, with higher rates of serious illness than the general population, there is an urgent need for strategies to provide culturally tailored palliative and end-of-life care interventions for seriously ill ANAIs. However, ANAIs are far less likely than their US peers to use palliative care, including advance care planning (ACP), which involves discussing patient values and goals to align care with patient preferences. ACP leads to better outcomes for patients, their families, and health systems, including decreased depression, anxiety, and grief, fewer non-beneficial end-of-life treatments, and reduced cost. ACP is typically documented in advance directives (ADs) that specify patient preferences for life-sustaining treatments and who can make medical decisions on their behalf. Yet, less than a third of seriously ill US adults have ADs, and ANAIs age 55 and older are only half as likely to have ADs as their White peers. Previous research suggests that ANAIs will engage in ACP and complete ADs when given access to timely and culturally appropriate ACP conversations, but no ACP communication interventions have been rigorously tested with ANAIs. Our team used community engagement methods to culturally tailor an ACP communication intervention and pilot the tailored intervention—Jumpstart ANAI—with 68 seriously ill adult ANAIs at Southcentral Foundation (SCF), a Tribal health system in Alaska. We recruited 97% of the target sample (n=70) and retained >75% of patients at follow-up. We also found that 95% of patients stated that Jumpstart ANAI helped them to have ACP conversations with their primary care providers. This project expands upon a strong community-academic partnership to implement Jumpstart ANAI in the Tribal health system and evaluate it using an innovative type 1 hybrid effectiveness-implementation approach. Our specific aims are to: 1) Engage stakeholders to tailor an implementation plan for the Tribal health system that integrates Jumpstart ANAI into routine primary care practice; 2) Conduct a cluster-randomized trial with 40 primary care providers and 280 seriously ill ANAI patients to test the effectiveness of Jumpstart ANAI for increasing ACP as compared to usual care; and 3) Conduct a rigorous mixed-methods process evaluation using the Consolidated Framework for Implementation Research to assess barriers and facilitators to implementing Jumpstart ANAI system-wide. Improving access to and delivery of culturally appropriate evidence-based ACP is a high priority for Alas...