When youth with autism spectrum disorder (ASD) transition from school to adult services, they fall off a “service cliff.” To increase access to services, Drs. Burke (PI) and Taylor (Consultant) developed the ASSIST program, which teaches parents how to advocate for adult services on behalf of their youth with ASD. In a pilot randomized controlled trial (RCT: R34 MH104428), treatment group (versus control) participants demonstrated significantly improved knowledge of adult services, advocacy, and empowerment. Sons/daughters of treatment group participants had increased access to services. For advocacy services interventions like ASSIST to be equitable, they need to reach families who are at greatest risk for service disparities. Latinx youth with ASD are one such underserved population. Relative to White youth, Latinx youth with ASD receive significantly fewer post-secondary education, health, and employment services and face worse post-school outcomes. In addition to the barriers which hinder service access for all families, Latinx families face unique barriers to service access (e.g., language, cultural differences, citizenship, discrimination) making them a marginalized population. In this project, we are adapting the ASSIST curriculum and related measures for Latinx parents of transition-aged youth with ASD. Specifically, we will leverage ASSIST data and data from Latinx, non-ASSIST parents to inform adaptations to the ASSIST curriculum. We will also conduct pre-testing and a cross-cultural adaptation process to revise the ASSIST measures for Latinx families. We will test the adapted ASSIST curriculum with a randomized controlled trial to determine its feasibility, acceptability and efficacy on intervention targets (knowledge, advocacy, and empowerment) and outcome of interest (service access). This project is aligned with NIMH priorities by examining services from adolescence to adulthood (PA-21-199) and by adapting a program to improve mental health services for underserved populations NIMH 2020 Strategic plan). It is also responsive to the Interagency Autism Coordinating Committee core value of “equity” in reducing disparities with respect to cultural backgrounds. Further, if successful, it will be the first intervention to directly address service disparities for Latinx families of youth with ASD who are transitioning to adulthood.