Trauma has assumed a prominent role in contemporary medicine as an event that can significantly influence clinical variables such as morbidity, functional deficits and consequential disability, and mortality. Trauma is the principal cause of death in the population below 40 years of age in industrialized coun tries. Therefore, there is great interest in studying traumatic events from both the clinical and epidemiological viewpoints. The importance of trauma is exem plified by the fact that in many countries the trauma patient is first treated in specialized "trauma centers," in which the diagnostic and treatment processes are facilitated by the 24-hour presence of personnel having interdisciplinary competencies. Trauma in this context consists of any acute, often unexpected, condition. Many of the medical difficulties associated with trauma occur in a relatively brief period that spans from the first call for help to the initiation of first aid measures. A correct approach depends on the availability of experienced personnel. The first measures of aid must guarantee, above all, the patient's survival. The most critical, initial phases of care to trauma patients are represented by the triad: first aid, triage, and transport. Specific morbidity indices, whether anatomical, func tional or mixed, are indispensable elements for monitoring a patient's clinical evolution. The immediate availability of "essential" drugs is imperative to con front the clinical situations that often present in the acute post-traumatic phase."