Abstract Every day in the US approximately 100 people are injured by a firearm through violence1, and three-quarters of all homicides are firearm related1. Although firearm-related violence impacts all communities and populations, youth are high-risk for firearm-related violence, injury, and mortality. In particular, violently injured youth are highly susceptible to retaliatory firearm-related violence, as well as becoming violently re-injured or killed6. Therefore, the hospital has become a critical opportunity to prevent retaliatory violence in youth. At Virginia Commonwealth University (VCU) Health, we have adapted our comprehensive hospital-based violence intervention program, Bridging the Gap (BTG). BTG is a novel hybrid intervention model that capitalizes on the hospital-based intervention approach using a brief violence intervention to prevent retaliatory violence but also provides community-based support to youth and their families by providing 3-months of community case management to help ensure lasting change. BTG in its current form has shown promise for reducing aggression and violence-related risk factors. However, it is yet to be established if it is effective for reducing firearm-related violence, injury, and mortality for youth. To address the surge in firearm-related violence in youth (10-17 years), we have further adapted BTG to include a dual-generation firearm safety counseling program delivered in the home. Using a randomized control trial design, the present study aims to rigorously evaluate the effectiveness of BTG for preventing firearm-related violence, injury, and mortality among violently injured youth (N=220). Firearm-related violence, injury, and mortality outcomes will be assessed over 6 months using multiple sources of data (e.g., semi-structured clinical interviews, self-and caregiver-report assessments, and hospital-, state- and national-level databases). In addition to understanding BTG effectiveness for preventing firearm-related outcomes, we aim to understand what psychosocial mediators explain the reductions in firearm-related violence in response to treatment, and what moderators may reduce treatment effectiveness. These data will prove beneficial for developing and tailoring new and existing youth firearm violence prevention strategies.