Trauma is a major cause of mortality and morbidity worldwide. Methods of assessing outcome have evolved with management of trauma victims.The wide variety of scoring instruments available to assess the injured patient may be divided into three groups: anatomical, physiological and combined systems. Anatomical systems depend on an accurate description of the injuries sustained. Physiological systems measure the effects of injury on the patient's physiological reserves. Combined systems contain elements of both anatomical and physiological scores. Prospectively, scoring systems help in description, triage, treatment decisions and estimating outcome. Retrospective scoring is helpful in audit, in quality control, in comparing treatment methods or centres, and in identifying unexpected outcomes. Limitations may be inherent in the system or may reflect inaccurate or incomplete data collection.