Football injuries account for more concussions than any other sport in North America. A 1977 survey of high school football players in Minnesota found that 19% of players reported at least one concussion (characterized by loss of awareness) during a season. These results have not been confirmed in subsequent studies. This study sought to estimate the incidence of concussion among high school football players in our region, establish the frequency of the most common symptoms, and determine the duration of subsequent restriction from participation in the sport. The athletic boards of area high schools distributed a three-page survey to 450 high school football players. Of the 450 surveys distributed, 234 (52%) were returned, only 1 of which was excluded because of contradictory information. The incidence of concussion in football players was 47.2% (110/233, P < .001 versus a previously determined rate of 19%). Eighty-one of 233 players (34.9%) had multiple concussions. A total of 376 concussions were reported. The distribution of severity of the 376 reported concussive events was grade I, 87.8%; grade II, 9.9%; and grade III, 2.4%. Only 12 athletes were required to stop play for one or more games. The incidence of high school football players sustaining a concussion is much higher than previously established. The majority of these are mild (grade I) concussions. Further research is needed since multiple low-grade concussions may incur cumulative neuropsychologic impairments.