Cell Savers are used intraoperatively to decrease the risk of transfusion due to surgical blood loss. Blood collected from the operative field is anticoagulated, filtered, and stored in a reservoir. Once a set volume of blood has been collected in the reservoir, the blood is separated into its red blood cell and plasma components by use of a centrifuge. Red blood cells are washed with a crystalloid solution and then reinfused into the patient. Although the theoretical benefits of using a cell saver are attractive, the literature seems to be controversial with respect to efficacy and cost-effectiveness. The benefits are clear in patients undergoing fusions for scoliosis that involve more than 5 levels where blood loss is considered substantial. It is less clear in patients who undergo a more limited two to three level lumbar fusion.