A retrospective analysis was conducted on injury statistics compiled over 12 seasons, from 1982 to 1993 (2.55 million skier-days), at a Wyoming ski resort. The population at risk was determined by ticket sales per year. A total of 9749 skiing injuries was indexed by anatomic region and severity according to diagnosis on initial evaluation. Injury rates were then analyzed as a function of time. The injury rate remained constant at 3.7 injuries per 1000 skier-days during the 12 seasons. The rate of lower extremity to upper extremity injury decreased from 4:1 to 2:1 during the study period (P < 0.03). The ankle injury rate also decreased with time (P < 0.04). Ulnar collateral ligament sprains make up 7% of all injuries. Knee sprains in general account for 30% of all injuries. The incidence of anterior cruciate ligament tears increased as a function of time (P < 0.04) and accounted for 16% of all skiing injuries during the study period. The medial collateral ligament sprain was the most common injury, making up 18% of skiing injuries. Forty-seven snowboard injuries from the 1992 to 1993 season are also presented. Our injury statistics mirror those currently reported in North America, except our data reflect a higher incidence of knee sprains.