Background: Facilitators are often responsible for the implementation of public health programs, yet little is known about how they influence outcomes. Not-On-Tobacco (N-O-T) is a youth smoking-cessation program implemented by trained facilitators. The purpose of this study was to investigate teens' perceptions of facilitator characteristics and the relationship between those perceptions and program outcomes. Methods: Data were collected from N-O-T participants aged 14 to 19 who completed a survey about perceptions of facilitator characteristics that were linked to program outcomes 3 months post-baseline (n = 769). Eight facilitator characteristics were ordered, based on importance to participants. Chi-square tests measured differences in perceptions of facilitator characteristics according to race and sex, and an aggregate facilitator favorability score was created and analyzed in relation to program outcomes (smoking reduction or cessation vs increase/no change). Logistic regression was used to analyze facilitator characteristics' relationship to outcomes, controlling for race and sex. Results: Participants rated facilitator characteristics of trustworthy, cares about students, and confidential as most important. Girls consistently ranked facilitator characteristics as more important than did boys. There were few significant differences based on race, except that white students rated nonjudgmental to be more important than did nonwhite students. There were no significant findings from the logistic regression, but there was a significant relationship between the aggregate facilitator favorability score and favorable changes in smoking outcomes (reduction or cessation). Conclusions: This study provides insights into the facilitator characteristics that are important to teen participants. It demonstrates that teens' overall perceptions of facilitators contribute to their perception of how the program contributes to their success and program outcomes. (Contains 2 tables.)