PURPOSE:To report the prevalence of recent adolescent recreational and sporting activities and associated injury. METHODS:Data were collected during three school terms in 1997 using a validated questionnaire administered once only to 3538 girls and boys aged 11-12 years and 15-16 years. These students comprised 97.5% of the students in these age ranges in randomly selected state and private schools in the Adelaide metropolitan area (South Australia). Participants identified up to three recreational and/or sporting activities in which they had participated in the previous week. Data were collected on the nature and extent of participation, and on associated injuries. Participation and injury reports were summarized descriptively in gender strata in the two adolescent age groups and stratum specific odds ratios were used to explore injury risk. RESULTS:Subjects reported participating in 8997 sporting and/or recreational activities in the preceding week (an average of 2.5 participations per student). Over 140 sports and recreational pursuits were represented, incorporating organized and nonorganized activities undertaken in teams, social groups, or alone. Approximately 25% of adolescents reported at least one recreational injury. Injuries were mostly minor, reflecting soft tissue trauma and skin abrasions. Organized group sport incurred the highest risk of injury. There were marked gender and year level differences in injury risk in a number of common activities. CONCLUSIONS:These findings support the need for ongoing education regarding injury prevention and management.