ABSTRACT Globally there is a growing need to implement community-based services that support improvements in quality of life of autistic people. Early autism intervention is critical because it can significantly improve both child and family outcomes, but implementation gaps exist worldwide. These gaps are starkest in Africa, where by 2050, iven the lack of specialists in Africa, task shifting early autism intervention to non-specialists will be a key implementation strategy. Naturalistic Developmental Behavioral Interventions (NDBI), are a class of early autism intervention approaches, that can be effectively delivered by caregivers. Through a partnership between Duke University and the University of Cape Town, our team laid the groundwork for an innovative and scalable coaching intervention for young autistic children . We systematically adapted a caregiver coaching NDBI for the South African context in which coaching is effectively delivered by non-specialist Early Childhood Development practitioners employed by the Education Department. In the proposed study we will build on our foundational work by conducting a type 1 hybrid effectiveness implementation trial of the coaching intervention, delivered by non-specialists, within an existing system of care in South Africa. Our goal is to implement a feasible, scalable early autism intervention model in Africa by conducting research with culturally and linguistically diverse participants in community-based settings, that is inclusive of diverse stakeholder perspectives and incorporates task-shifting. In the proposed study, we will build on our current relationships with families, practitioners, and policy makers by formalizing these relationships and including other key stakeholder groups such as South African autistic self-advocates through a community-academic partnership, a key bridging factor in the EPIS implementation framework. The proposed project has three main objectives. First, to evaluate the real-world effectiveness of non-specialist delivered NDBI caregiver coaching for improving patterns of caregiver-child interaction and child developmental outcomes, and assess the cost- effectiveness of this approach. Second, to identify implementation determinants to inform scale-up. Third, to expand African autism research capacity to enhance scalability. This project also offers a unique opportunity to study variability in autism-related behaviors and phenomenology. We will therefore assess the degree to which response to intervention is moderated by caregiver and dimensional child characteristics. In addition, using an innovative digital assessment method, changes in dimensional quantitative measures of autism-related behaviors will be examined. Finally, cross-cultural differences in dimensional autism-related behaviors will be evaluated via comparison with existing quantitative phenotypic data gathered in U.S. studies. This study is timely and innovative and will inform scale-up of autism ear...