ABSTRACT Only slightly more than half (55%) of 4-17 year olds with significant mental health difficulties receive treatment. These are often not initiated until issues are significantly impacting the child and family. Nearly half of children with known mental health disorders and up to 80% of children with sub-clinical symptoms receive no treatment. This study aims to (a) develop methods based on electronic medical records data to identify early mental health needs in children 4-17 years of age and (b) conduct a pragmatic randomized trial in two non-academic health care systems to test a mental health family navigator model to promote early access to, engagement in, and coordination of needed mental health services for children and adolescence. Phase 1 of the study would focus on the development and refinement of a natural language processing (NLP) tool to identify symptomatic 4-17 year olds with no diagnosed mental health disorder(s). The tool would identify patients with documentation of mental health symptoms or complaints in the free text of a progress note from a recent primary care or urgent care visit. Phase 2 of the study would focus on conducting a pragmatic randomized trial comparing intervention and usual care arm patients enrolled from Kaiser Permanente (KP) Washington and KP Northern California. The trial will enroll 200 patients per arm (n=400). The navigator model to be implemented and tested will include three groups based on recent visits recorded in the electronic health record. Those with: (1) a new mental health diagnosis; (2) new mental health medication ordered, no mental health diagnosis; (3) no new mental health diagnosis or medication (symptoms identified by NLP tool). The study intervention will offer 6 months of support to the family by a mental health navigator (social worker). The navigator will perform an initial needs and barriers assessment with the family around mental health services, conduct ongoing motivational interviewing around mental health care, provide up to 4 bridging psychotherapy sessions (when appropriate) via clinic-to-home video visits, help the family find and schedule with appropriate mental health providers in the community, reach out ad hoc if mental health appointments or medication refills are missed, stay in contact with the family for 6 months. The primary outcome is percentage of youth with at least 4 psychotherapy visits in the 6 months following the initial visit. The secondary outcome is the percentage of youth with >=80% medication adherence over the 6 month follow up period. We hypothesize that the intervention arm will have higher rates of psychotherapy use and medication adherence compared to the control arm. We will also assess medication adjustments, initiation of psychotherapy or medications, and (intervention arm only) change in self-efficacy in navigating the mental health care system over 6 months. All primary analyses will follow an intent-to-treat approach. A waiver of consent will be obtained to include data for all individuals offered the intervention in the analysis, regardless of the amount of intervention (?dose? of navigation) received.