Coaching and Leadership in Autism Support Settings (CLASS) - PROJECT SUMMARY The purpose of this study is to test the clinical effectiveness of the Research Units on Behavioral Interventions in Educational Settings (RUBIES) program relative to educator psychoeducation on externalizing behaviors of autistic children in public elementary schools as well as the effects of an organizational implementation strategy, Helping Educational Leaders Mobilize Evidence (HELM), versus an implementation attention control on RUBIES sustainment. The increased prevalence of autism spectrum disorder (1 in 36 children) in the United States along with the exorbitant cost of care of supporting one autistic individual with and without intellectual disability across their lifespan ($2.4 and $1.4 million, respectively) creates a sense of urgency to improve outcomes for autistic children. Publicly funded education systems are the primary setting in which autistic children receive services; however, behavior management strategies that educators can use for this population often are extremely time-consuming and resource-intensive. Schools carry unique service delivery opportunities and constraints that necessitate careful evaluation of programs and practices in that context. There is a dire need to support schools to build systems and structures to support implementation with fidelity and sustainment over time. To address this, we propose a cluster-randomized, hybrid type 2 effectiveness-implementation trial with schools randomized to: 1) educator coaching in RUBIES and school participation in HELM; 2) educator coaching in RUBIES and school participation in an implementation attention control (IAC) condition; or 3) a control arm incorporating an active clinical comparator, educator psychoeducation. We will enroll 40 schools, 120 educators, and 120 autistic children. We aim to: 1) test the clinical effectiveness of RUBIES, relative to educator psychoeducation, on externalizing behavior of autistic children in public schools; 2) test the effects of an organizational implementation strategy (HELM) versus implementation attention control (IAC) on RUBIES sustainment; and 3) evaluate the mechanisms of RUBIES and HELM on child and implementation outcomes. The proposed work directly responds to high priority research areas of the US Department of Health and Human Services Interagency Autism Coordinating Committee’s Strategic Plan for Autism Research, which calls for expanded research on the translation of proven-efficacious interventions into the community, NIMH Strategic Priority 3.3 to test interventions for effectiveness in community practice settings, and NIMH Strategic Priority 4.2 to expedite adoption, sustained implementation, and continuous improvement of evidence-based mental health services. If successful, this study will have substantial public health impact because it will produce an effective intervention for a prevalent problem among a high impact population in schools across the USA and will determine how to sustain this (and other) intervention(s) with high fidelity, to the betterment of health.