This study examined the effect of community service program-quality on changes in adolescents' intentions to volunteer. Based on the literature, volunteering intentions were expected to increase by programs with high quality community service activities (e.g., instructive activities) and educational activities including reflection. Adolescents (N= 361; M age = 15.67; SD = 0.74) divided in three groups were compared: community service students who were randomly assigned to a reflection intervention (N= 172) or no intervention (N= 142), and students who did not perform community service (N= 47). Data were collected before and after community service, and a half year after finishing community service. Results showed that adolescents' volunteering intentions increased when performing high quality service activities. When performing low quality service activities, volunteering intentions declined, unless adolescents received the reflection intervention. Thus, high quality activities and reflection are key community service characteristics for stimulating adolescents' volunteering intentions.