Nonoperative (NON-OP) management has been accepted as the treatment of choice for stable patients sustaining blunt liver injury. The objectives were to evaluate the results and changes in the treatment of grades 3 and 4 liver injuries and to determine the impact of NON-OP management on mortality. This was a retrospective review of all grade 3 and 4 blunt liver injuries treated during a 15-year period. One-hundred and twenty-eight consecutive patients (27 NON-OP) were analyzed. Thirty-four patients died in the OP group (33.7%). Nonsurvivors were older (28 versus 39 years), had lower revised trauma score (RTS), higher injury severity score (ISS), and higher transfusion requirements. Six patients failed NON-OP management (22.2%). The mortality rate in the NON-OP group was 0%. NON-OP was associated with a 23.5% reduction in mortality. Unnecessary OP management of grades 3 and 4 liver injuries should be discouraged.