This timely volume proposes that to fully understand, and then intervene to improve participation in out-of-school (OST) programs, issues of access, enrollment, and engagement must be considered, and in the context of program quality. Contributing authors unpack the construct of participation, posing a three-part equation, participation = enrollment + attendance + engagement, and examine these three critical components of overall participation in out-of-school time programs. Chapters provide research-based strategies on how to increase participation, and how to define, measure, and study it, drawing from the latest developmental research and evaluation literature. Volume editors Heather B. Weiss, Priscilla M. D. Little, and Suzanne M. Bouffard outline the main theme with an introductory review of participation as a three-part construct of enrollment, attendance, and engagement and show how this understanding of participation can help stakeholders to maximize participation in and benefits from programs. Other contributors discuss research in OST from the perspective of youth; similarities and differences in participation and outcomes across social ecologies; how youth and family characteristics can identify which youth are most likely to participate in organized activities; recruitment and retention strategies for OST programs; measuring attendance in OST programs; and encouraging progression from attendance to active engagement The editors and contributors to this volume provide compelling information that encourages practitioners, researchers and evaluators, policymakers, and funders, all working to improve the lives of young people through regular, meaningful attendance in the diverse set of out-of-school time programs operating throughout this country, to better understand participation-and how to use that understanding to increase enrollment, measure and sustain attendance, and engage young people to reap the full benefits of "being there." This is the 105th volume of the Jossey-Bass quarterly report series New Directions for Youth Development. Click here to view the entire catalog of New Directions for Youth Development titles.