This application for a Practice-based Suicide Prevention Center (PAR-20-286), ETUDES (Enhancing Treatment and Utilization for Depression and Emergent Suicidality) is a competitive renewal of our current Alacrity P50. We aim to address the crisis in adolescent suicide, with special attention to Black youth, for whom the rate of suicide attempts has increased more rapidly than in any other demographic group. We will develop and test effective methods for identifying and intervening with youth at risk for suicide that can be readily deployed in pediatric primary care (PPC). We focus on PPC because most youth visit PPC annually, youth are routinely screened annually for depression and suicidal risk, and mental health treatment delivered in primary care can decrease disparities in access and outcomes. We focus on the following strategies to reduce suicidal behaviors: (1) improved identification to complement screening; (2) promote linkages to services and safety planning; and (3) targeting risk factors for depression and suicidality to prevent the onset of suicidal crises. In the first component of our signature R01, we will develop prediction models that combine machine learning algorithms using EHR data and mobile sensing to improve our detection of imminent suicidal risk in a cohort of 2,000 youth, recruited from PPC. In the 2nd component of the R01, we will conduct a randomized controlled trial on a subset of this cohort, 900 suicidal youth, comparing usual care to a suite of tools that we have developed to help PPC providers assess and manage suicidal youth. In previous work, these tools increased physician referrals to mental health and engagement in treatment, and reduced suicidal behavior. We propose three R34s that target domains that increase risk for depression and suicidality, namely, online victimization, low activity/anhedonia, and poor sleep. To address the national crisis of rising suicidal behavior in Black youth, we will recruit a sample that is at least 35% Black, and apply implementation science methods to ensure that all assessments and interventions are acceptable and effective for Black youth and their families. Moreover, our methods of identification and interventions target probable sources of racial disparities in suicidal behavior, namely, treatment access, online victimization, low activity, and poor sleep. This Center renewal convenes a diverse, interdisciplinary team, with expertise in clinical trials and longitudinal studies, machine learning, mobile sensing, health disparities, and implementation science. All aims are guided by collaboration with stakeholders, some of whom play leadership roles in the Center. Primary to the Center’s mission is the training and support of a diverse group of 10 early career scientists who play critical roles in Center projects. If successful, Center projects should yield predictive algorithms for imminent suicidal risk to complement annual screening, a care pathway for suicidal adolescent...