This participatory, pragmatic efficacy-implementation trial evaluates the impact of Promoting Community Conversations About Research to End Suicide (PC CARES) on adult participants and the adults and youth they are ‘close to’, who we hypothesize will benefit from the intervention. For sustainability, the project also identifies barriers and enablers to community implementation of PC CARES in rural Alaska Native (AN) communities. Using a multilevel growth model, we examine the changes in suicide prevention knowledge, self-efficacy, collaborations for a ‘community of practice’ (CoP) and prevention-oriented behaviors of adult PC CARES participants (n=250) over time (7 timepoints), testing for moderating effects of dosage (e.g. #LCs attended), community ‘readiness’; cross-sector participation on outcomes to inform future PC CARES implementation (AIM#1). Over the same time periods in six randomly selected communities, our communitywide adult and youth measures assess the community-level mechanisms of change (social diffusion), and for the first time, track youth outcomes (AIM#2). We hypothesize that PC CARES will encourage adults to develop a collaborative relationships within a CoP to implement upstream suicide prevention best practices (SPBPs) in support of youth in their lives. Using community level social network measures, we document the number and type of interactions reported by adults (n=450) over time, capturing social diffusion by comparing the knowledge, self-efficacy, CoP and prevention-oriented behaviors of (1) PC CARES participants, (2) non-participants who are ‘close to’ participants and (3) others, unrelated to participants (comparison group). To assess youth impact (n=300, ages 12-19), we measure youth reported supportive adult interactions and connectedness (over 7 time points), and pre-post perceived social support, family and community protective factors, comparing outcomes for youth who are ‘close to’ participants versus 'unrelated' youth (comparison group). AIM#3 combines community-engaged methodologies and evidence-based implementation science frameworks to examine the barriers and enablers of PC CARES implementation in AN communities. The proposed study fulfills the priorities of the Intervention Research to Improve Native American Health (PAR-17-496) because it: (1) tests the effectiveness of a promising suicide prevention intervention developed with and for AN communities; (2) builds on cultural and community knowledges as well as scientific best practices; (3) examines adult participant outcomes and diffusion at a community level, (4) tracks the impact of adult prevention behaviors on youth-reported protective outcomes, which promote mental health, safety and buffer suicide risk, and (5) by partnering with a successful educational pathway for AN community mental health workers, our study of barriers and enablers of implementation will pave the way for feasibly scaling PC CARES to other rural and remote AIAN communities who s...