• This study investigated reasons for adolescents' attrition from school-sponsored sports teams and the relationship between attrition and intention to participate in organized and nonorganized sports in the future. Of 674 high school student athletes, 26% dropped off at least one team in 1989-1990, and overall attrition increased to 29.8% when attrition from more than one sport was considered. Attrition was higher among black students, students reporting an athletic injury, those injured playing football, and those sustaining a knee injury. Injury was cited as the most frequent reason for attrition, followed by being cut from the team, "other reasons," needing to get a job, inconvenient game or practice schedule, and needing more time to study, although the main reason for attrition also varied by sport. When athletes were classified according to externally precipitated attrition, athlete-initiated attrition, or completion of the sports season, no differences were noted in the three groups' intent to engage in organized sports in the future. However, the group with externally precipitated attrition expressed a stronger intent to engage in nonorganized sports in the future than the other two groups.