Engaging Mental Health Services for Preschoolers at Risk - Most mental health (MH) disorders develop in early childhood but are not clinically identified or treated until later—delaying treatment services that could prevent the enduring effects of long-term MH problems. Moreover, children from low-income families and those with demographic differences exhibit higher rates of persistent MH disorders and are at greater risk for lags in identification and treatment creating a mental health gap in services. Head Start has shown early school success for low-income children, aged 3-5 years. Head Start monitors for early childhood MH symptoms, yet studies have found that when detected, only those most impaired are referred for treatment. In our research, we identified multiple barriers that preclude early treatment among Head Start preschoolers with developmental concern. We showed that caregivers encountered system barriers of Head Start teachers and primary care providers (PCPs) falling behind in referrals for intervention, and caregiver beliefs about stigma, their limited knowledge and distrust of healthcare hindered early engagement in services. Studies on MH treatment obstacles for low-income people, and demographic differences illustrate similar barriers to those found among Head Start preschoolers with developmental concern. Our team developed and tested a peer-based family navigator program for Head Start preschoolers with developmental concern. Navigators used trust and empowerment to increase caregiver advocacy thereby leading to improved professional alliances and treatment. A navigator program for those with primary MH concern has not been trialed. In this R34 pilot effectiveness trial, we propose to take this next critical step by tailoring and preliminary testing in a case series the Navigate-Train-Referral-Intervention Mental Health (NTRI-MH) intervention to promote access, engagement, coordination, and optimization of services for preschoolers with MH symptoms. In Aim 1, we will use focus group feedback from caregiver, navigator, Head Start teacher, and PCP stakeholders (n=30) to adapt NTRI-MH and create a web-based dashboard to monitor outcomes. Then, conduct a feasibility study for caregivers of Head Start preschoolers with MH symptoms, guided by family navigators and referrals by Head Start teachers and PCPs (n=20). In Aim 2, we will pilot test NTRI-MH for caregivers of preschoolers with MH symptoms compared to an active control group of caregivers who receive child behavior training (n=86). We will trial the effectiveness of the NTRI-MH mechanisms of caregiver beliefs on MH, empowerment, and professional alliances on family functioning and child emotion regulation. If the aims of the project are achieved, this study would have a large impact on early MH service use for low-income and those demographic differences with the potential to improve child MH outcomes.