This study examined the effectiveness of the First Step to Success (FSS) early intervention program with four Native-American students, their teachers, and their parents on (a) targeted students' problem behaviors, (b) class-wide student behaviors, and (c) teacher behaviors. Participant teachers and parents were also interviewed to gather their perceptions of the FSS program. The results of direct observations of targeted students' play behaviors on the playground revealed that the FSS program had a significant positive affect on all participant students' social play behaviors. As soon as the intervention started, all participant students' social play behaviors significantly increased and their nonsocial behaviors decreased. All participant students showed higher levels of social play behaviors as soon as the intervention was initiated. Substantial decreases in problem behaviors were also reported by two teachers. Some positive changes in class-wide student behaviors and teacher behaviors were reported by the participant teachers. All but one parent reported significant changes in problem behaviors of targeted students. They all were highly satisfied with the program and rated it as easy to use. Limitations of the study and directions for future research are discussed.