OBJECTIVE: To analyse the types and causes of injuries associated with recreational snowboarding and to compare these with the injuries seen in alpine skiing. DESIGN: Prospective case series. SETTING: Rural hospital near three large ski resorts. PATIENTS: All people presenting to the Emergency Department with an injury caused by snowboarding during two ski seasons (1988-90). Of the 115 injured snowboarders identified, 73 (63%) completed the questionnaire. Information on the other patients was obtained from the hospital emergency records. Information was also obtained on seven alpine skiers who collided with snowboarders. RESULTS: Of the snowboarders 87 (76%) were male, and the mean age was 20.3 years. A total of 132 injuries were documented. Of the respondents to the questionnaire 83% reported that their fitness level was excellent or above average, 36% had never been on a snowboard previously, 25% were in their first year of snowboarding, 39% reported excellent snow conditions, 59% reported light traffic on the hill, and 7% had consumed alcohol before their accident. Injuries were equally divided between the upper body and the legs, 75% of the lower-limb injuries involving the left (lead) leg. Significant differences were noted between the patterns of injuries in snowboarding and alpine skiing: snowboarders were less likely to have lacerations (0% v. 8% respectively), boot-top contusions (0% v. 4%), thumb injuries (1% v. 10%) and knee sprains (14% v. 27%) and more likely to have spinal injuries (12% v. 4%), foot or ankle injuries (28% v. 5%) and distal radius fractures (10% v. 1%). CONCLUSIONS: Snowboarding is associated with a unique pattern of injuries, the knowledge of which could influence snowboarder education, accident prevention and equipment design. Additional research is needed to understand better the types, causes and rates of injury associated with snowboarding.