This notice of funding opportunity (NOFO) is a call to action in response to the youth mental health crisis in the United States. NIMH seeks applications that will study methods to increase access to, and quality of, empirically-supported practices for youth mental health. Applications may address research related to: optimizing assessment, intervention and service strategies; overcoming challenges related to workforce shortages and waitlists for treatment; integration of treatment and preventive interventions into settings where youth are most likely to be identified as needing care (e.g., schools, pediatric medicine, community organizations, social services, and juvenile justice), and service interventions that address systemic barriers to access and quality of mental health care (e.g., structural, policy, organizational, value in terms of cost/financing, management).