Treatment of patients with multiple trauma is known to require validated established algorithms, experienced medical staff and intensive interdisciplinary cooperation between the medical disciplines. In order to predict the risk for potential complications and mortality, adequate assessment of patients with multiple trauma is crucial for further treatment decisions. Therefore, different scoring systems have been developed to assess injury severity and to predict the potential outcome after multiple trauma. These scores have in common that the severity of trauma is converted to a numeric value simplifying the physiological reality in general. But the anatomic as well as physiological impact after multiple trauma can hardly be represented comprehensively by a single numeric value. Consequently, the established scores can only be safely interpreted, if the individual limitations of each scoring system are known.