The goal of this paper was to document the injury rate in modern competitive karate. A prospective recording of the injuries resulting from 2,837 matches in three consecutive World Karate Championships (WKC) was performed. Eight hundred and ninety-one injuries were recorded, with an incidence of 0.31 injuries per match or 157.03 injuries per 1,000 athlete exposures. Occurrence of injuries was higher among lighter categories, under 60 kg in males (0.56) and under 53 kg in females (0.42). Punches (737, 82.7%) caused more injuries than kicks (75, 7.3%). The injuries were most commonly located in the face (646, 72.5%) followed by the head (103, 11.6%) and lower limbs (57, 6.4%). The injuries consisted primarily of contusions (448, 50.3%) epistaxis (144, 16.2%) and lacerations (122, 13.7%) followed by concussions (34, 3.8%) and sprains (31, 3.5%). There was some kind of external haemorrhage in 296 injuries (33.7%). The injury rate was similar in the three WKC but the number of severe injuries declined from 1996 to 2000. We conclude that competitive karate is associated with a relatively high injury rate; in one in every three matches medical attention is required, but mainly for minor injuries. Severe injuries are rare.