We recently completed an NIMH R34 in which we piloted a patient- and provider-informed tablet-based toolkit designed to facilitate delivery of Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) – a treatment that was selected because it addresses a wide range of symptoms using techniques shared by other treatments for emotional and behavioral disorders. The tablet-based toolkit consists of numerous components (e.g., videos, interactive games, drawing applications) that are designed to facilitate provider-patient interactions in a way that enhances children's engagement and supports adherence to the treatment model. The tablet-based toolkit was very well received by children, caregivers, and providers in our pilot work. Moreover, all benchmarks for feasibility outlined in our NIMH R34 application were met or exceeded. We now propose to conduct a hybrid effectiveness-implementation trial to examine the extent to which the tablet intervention may improve fidelity, engagement, and children's mental health outcomes. We will conduct a randomized controlled trial with 250 mental health providers and 360 families in partnership with dozens of clinics in the Carolinas and Florida. Providers will be assigned randomly to tablet-facilitated vs. standard TF-CBT. Youth aged 8-16 years with clinically elevated symptoms of PTSD will be recruited. Baseline and 3-, 6-, 9-, and 12-month post-baseline assessments will be conducted by independent, blind evaluators. Sessions will be videorecorded for observational coding of engagement and fidelity by independent raters blind to study hypotheses. We will also examine costs and conduct semi-structured interviews with families, providers, supervisors, and agency leaders to inform future dissemination and implementation initiatives. Technology-based resources that are scalable, easy to use, and designed for efficient integration into everyday practice may have sustained national impact. The return on investment of these initiatives will ultimately rest on their potential to improve the spread of best-practice treatments and the quality with which they are delivered to the children who need them.