Participation in student peer leader roles, roles in which more senior students serve as mentors and educators to their peers, have continued to grow in their application and importance to institutions of higher education around the globe. Using a theoretical approach based in Legitimate Peripheral Participation and drawing from the International Survey of Peer Leaders, our paper explored the role of the quality and quantity of participation in important outcomes of the college experience: leadership development, skill development, and academic success. The results showed that the number of hours per week spent on peer leadership activities and the total number of peer leadership positions contributed to positive quality of engagement and enhanced students' academic outcomes, overall leadership skills, and career readiness. Moreover, findings showed that the quality of engagement moderated the influences of the quantity of participation particularly for measures of academic success. As students develop relationships with faculty, staff, and peers throughout their time in peer leader roles and feel a deepening sense of connection and belonging to the college or university, students in peer leader roles become fuller participants in the academic community and, as a result, develop the knowledge, skills, and ways of doing, thinking, knowing, and being that are critical for student success.