Grounded in social cognitive theory, the purpose of this study was to examine leaders' and students' perspectives of factors that contribute to effective voluntary after-school physical activity clubs. Data were collected over two-years via field observations (n= 115) and interviews with students (n= 278) and adult leaders (n= 126). Results highlighted interconnections among personal and environmental facilitators such as enthusiastic and caring leaders, multidimensional recruiting strategies, supportive and friendly club climates, and culturally relevant physical activities. Structural barriers such as a lack of administrative support, student hunger, and inadequate transportation options were also identified by leaders and students. While previous after-school physical activity club research has focused primarily on measuring physical activity increases, these students and leaders voiced valuable perspectives that contribute to understand why some initiatives fail and others succeed from a social cognitive theory perspective.