The aim of the study was to assess the role of non-operative treatment in haemodynamically stable patients with liver trauma. Over the period from 1996 to July 2000, out of a total of 2,048 patients with abdominal trauma, 124 open and 1,924 closed, we observed 77 hepatic lesions, consisting of 55 closed traumas and 22 penetrating traumas. Non-operative treatment was implemented in 18 patients (32.7%) with closed liver traumas. In addition to serial clinical examinations of the abdomen, the patients receiving non-operative treatment were submitted to thorough haemodynamic monitoring and complete blood counts in the intensive care unit. After an abdominal CT scan at entry, patients were submitted to abdominal ultrasonography 6, 12 and 24 hours after admission. Only two patients required transfusions, one presenting a pelvic fracture and the other a triple fracture of the femur, tibia and fibula. There was no mortality. A biloma was present in one case, successfully treated by means of a US-guided drainage puncture. It is patients with major cranial traumas that pose most problems for conservative treatment. Fifty percent of non-therapeutic laparotomies in our series were performed in patients with severe cranial traumas. It is precisely in these patients that an improvement in diagnostic capability is most desirable.