In order to assess the extent of the sports injury problem, it is necessary to identify both the incidence and severity of sports injuries. In the literature, the severity of sports injuries is usually described on the basis of 6 criteria: (i) nature of sports injury; (ii) duration and nature of treatment; (iii) sporting time lost; (iv) working time lost; (v) permanent damage; and (vi) monetary cost. It is important to include information on the severity of injuries in a sports injury registration system. This kind of information will help to set targets for preventive strategies. The more severe the injuries sustained, the higher the priority will be to prevent these injuries regardless of the injury incidence. When assessing injury severity one should take into account that, in order to enhance the comparability of research data, uniform definitions are also important in this area of sports injury surveillance. This paper briefly discusses the 6 criteria used to describe the severity of sports injuries.