Recent advances and the technical options that have lately become available in the surgical treatment of spinal injuries mean that clear definition of the indications is essential. Precise observation and classification of each injury to the cervical spine are of paramount importance for this purpose, to allow the comparison of proposed methods of treatment and of the results obtained with them. There are a number of classification systems for injuries to the cervical spine, none of which, however, is generally accepted. These classification systems are based on different criteria, such as nature of the accident at which the injury was sustained, neurologic deficits, morphological criteria, the concept of instability, and implications for treatment and prognosis. These criteria, however, hardly allow the classification of most of the injuries affecting the upper and those affecting the lower cervical spine in a single system. Therefore, the authors propose a system of their own, which draws on the principles of classification suggested by the ASIF for fractures of the extremities. According to this proposed new system, injuries are divided into those of the upper and those of the lower cervical spine, and each of these two main groups is further divided into three subgroups. In the case of the lower cervical spine, injuries are classed according as whether they affect the anterior or the posterior section of the spine more, or both to the same degree. Beyond this, injuries are subdivided with reference to whether they affect primarily bone, bone and ligament equally, or primarily ligament. Further subdivision by severity and implications for treatment allows more detailed differentiation. This classification system is based on the analysis of over 200 cases of injury to the cervical spine treated by the authors and of cases from the literature.