Peer providers are a promising practice for transition-age youth community mental health treatment engagement and support, yet little is known about the experience of being a young adult peer provider or what helps to make an individual in this role successful. Utilizing a capital theory lens, this study uses data from focus groups (two with young adult peer providers and two with their supervisors) to examine facilitators of young adult peer provider success in community mental health treatment settings. Eight factors were identified as critical to young adult peer provider on-the-job success: persistence, job confidence, resilience, job training, skilled communications with colleagues, regular and individualized supervision, support from colleagues, and family support. Findings suggest that young adult peer providers may benefit immensely from an agency level focus on fostering social organizational capital as well as more individualized efforts to increase cultural, social, and psychological capital through training and supervision.