Substance use among adolescents is associated with a range of negative outcomes and risk-taking behaviors. Identifying and intervening early is essential to reducing associated risks in adolescence and adulthood. New approaches are needed to equip youth-serving systems with tools to identify and respond to substance use. Screening, Brief Intervention, and Referral to Treatment (SBIRT) has emerged as a promising public health framework and there is a growing research interest in effective adaptations for its use with adolescents. However, healthcare settings, schools, and other community-based settings are slow to adapt SBIRT, citing gaps in knowledge and capacity to deliver evidence-based substance use prevention and early intervention. Further, these settings and the surrounding communities often lack the treatment and other prevention and recovery support resources needed for youth who screen as high-risk. Integrating young adult peers with personal lived experience of substance use recovery may meet this practical need. By drawing upon their shared experiences and skills developed in recovery, young adult peers can provide developmentally appropriate screening and intervention support to youth - while also providing urgently needed skills and time to under resourced settings. This article describes the value of young adult peer roles in expanding youth substance use prevention and early intervention, and features Project Amp as an example. Project Amp was designed as an extended, four-session brief intervention for low to moderate risk adolescents, delivered by trained young adult peers. Project Amp draws on best practices from peer recovery support and prevention and early intervention approaches such as SBIRT.