ABSTRACT In this SBIR Phase II we will design, integrate, and evaluate implementation protocols in both primary care and behavioral health for the pediatric adaptation of the clinical Mental Health Quotient (cMHQ), a comprehensive transdiagnostic mental health assessment tool developed in Phase I, along with a short screener called the MHQ-10. This work will be done in collaboration with the UC San Diego ImplementatioN Science and Team Effectiveness in Practice (IN STEP) Children’s Mental Health Research P50 ALACRITY Center and Rady Children’s Hospital San Diego (RCHSD), and will test the feasibility, acceptability, and effectiveness across two Rady pediatric primary care clinics and one mental health referral hub. The majority of instruments presently in use have numerous challenges including a lack of insight into the individual’s specific symptom profile, particularly missing many of the emerging symptoms in adolescents, as well as lack of insight into positive aspects of the patient, their lifestyle, traumas, adversities and other factors that can give the clinician a whole person view. The pediatric MHQ-10 is a first line screener to be offered in primary care that overcomes limitations of current short screeners by incorporating emerging symptoms in adolescents as well as positive capacities to position individuals on a mental wellbeing scale that enables more precise triage. The pediatric cMHQ will be offered to those recommended for intervention by the MHQ-10 or those presenting for behavioral health challenges and overcomes the many limitations in the current landscape. Through a single compact assessment, it captures a comprehensive transdiagnostic symptom profile mapping to ten disorders, positive/protective life factors, lifestyle, life traumas and adversities to generate a vetted clinician report that includes a score of their aggregate mental wellbeing that can track their preclinical trajectory and provide guidance to the clinician. However, beyond the design of the assessment itself, the success of any new assessment within a hospital or clinic depends crucially on how it is embedded in the workflow and the consequent patient and clinician experience. This involves key criteria such as when and how patients are presented the assessment, how they are encouraged to complete the assessments, when and how doctors are presented the reports, and how they are guided to use the reports during the appointment. In this Phase II SBIR we will use an innovative, participatory implementation research method of co-design (brainwriting premortem) to develop a powerful workflow for integration of the pediatric MHQ suite within primary care and behavioral healthcare at RCHSD. This workflow will be designed to flexibly fit within a range of electronic health record platforms although it will be specifically implemented for Epic which is used at Rady. This will be followed by a multi-dimensional evaluation of implementation that will form the basis f...