There is growing awareness that the built environment and transportation affect many aspects of individual and community well-being and health. Built environment and transportation planning and decision-making, however, rarely integrate robust engagement and input from youth, particularly racially/ethnically and economically diverse youth, despite the likelihood that such planning and decisions will affect their futures. Strategies are needed that prepare, engage, and ultimately empower youth in changing systems, processes, and programs that promote equitable mobility access and opportunity for youth now and in these futures. This article describes the development, implementation, actions, and impact of the Youth for Equitable Streets (YES) Fellowship program, through the perspective of the program participants, including the youth (the Fellows), program manager, and program evaluator, focusing on key factors for making this work youth-centered and oriented to successfully influence social change in transportation for mobility justice.