The after-school setting is recognized as an important context within which to promote health-enhancing physical activity of children and young adolescents. In fact, the after-school setting can provide up to a third of a child's recommended daily activity levels (Trost et al., 2008). Although there has been increased interest in, and the development of, after-school programs (ASP) to boost activity levels, this area of intervention is still in its infancy. The purpose of this tutorial is to outline potentially effective ASP characteristics and provide practitioners with considerations regarding program design and monitoring of program-related outcomes. Based on findings from a comprehensive review of ASP to increase physical activity (Beets et al., in review), the following characteristics are related to effective programs: activities are designed to elicit a moderate or above intensity level, are enjoyable and culturally tailored, are transferable to outside the school-setting; program staff are trained in instructional skills related to promoting activity; staff turnover is minimized; and attendees are provided transportation from the after-school setting to home. Notably, the latter characteristic is essential, in that a lack of transportation can reduce attendance rates by half (Robinson et al., 2003). After-school staff must be provided on-going training to prepare them for working with youth in a physical activity setting. These trainings should include detailed descriptions of the activities used in the ASP with a booklet or manual available for program staff. Training of staff should also include culturally specific concepts related to motivation of youth to be physically active and teaching strategies associated with quality instruction. Consistent trainings may also assist in staff morale and thus decrease staff turnover. Ongoing monitoring of intensity levels during activities, through the use of heart rate monitors, accelerometers, or other measurement devices, is required in order to ensure attendees and staff members are adhering to prescribed intensity levels. After-school programs can be an effective means to improve physical activity levels. Attention to these elements will create a foundation of solid program design and monitoring to ensure beneficial program outcomes.Keyword(s): exercise/fitness/physical activity, health promotion, physical education PK-12