Even though many adolescent smokers want to quit, it is difficult to recruit them into smoking cessation interventions. Little is known about which adolescent smokers are currently reached by these measures. In this study we compare participants of a group-based, cognitive behavioral smoking cessation intervention with adolescent smokers who decided against participating.Within a non-randomized controlled trial, data of 1053 smokers (aged 11-19) from 42 German secondary schools were analyzed. Of these smokers, 272 were recruited into 47 courses of the intervention. An in-class information session, individually addressing potential participants, and incentives were used as means of recruitment. Personal predictors of participation were analyzed using regression analyses and multivariate path analyses to test for mediation.In the path analysis model, nicotine dependence, quit motivation, and a previous quit attempt were directly positively related to participation. Heavier smoking behavior was indirectly positively associated with participation through nicotine dependence and negatively through quit motivation, yielding an overall positive indirect effect. The positive effect of a previous quit attempt on participation was partially mediated through nicotine dependence and quit motivation. The proportion of smoking friends were indirectly positively related to participation, mediated through nicotine dependence.Since adolescents with heavier smoking behavior and stronger nicotine dependence are less likely to undertake a successful unassisted quit attempt, the reach of these young smokers with professional cessation interventions is desirable. Further measures to improve the recruitment of those currently not motivated to quit have to be examined in future studies.