Abstract
This special issue of the Journal of Early Adolescence presents research exploring the social and motivational processes thought to contribute to early adolescent engagement and participation in afterschool and out-of-school time as well as to targeted proximal and more distal developmental outcomes. Papers in the special issue address three broad themes, including (1) the role of internally and externally regulated motivation in joining programs and sustaining participation over time; (2) how programs may meet the developmental and relational needs of participants; and (3) social processes as mediators of proximal outcomes. Directions for future research on social and motivational processes in after-school programs are discussed.