To avoid homologous transfusion in spinal fusion surgery, acute normovolemic hemodilution was combined with controlled hypotensive anesthesia. Patients were kept hemodiluted, not only during surgery, but also after surgery by delaying transfusion until the next morning or later. Transfusion decisions were made by clinical judgment rather than by preset value (ie, 10 g/dl). Other techniques used in this protocol were preoperative autologous blood donation and intraoperative salvage of shed blood. Only 4 of 119 patients (3.4%) required homologous blood, compared to 25 of 29 patients (86%) in 1982, at which time none of these techniques were used. The average hemoglobin on the seventh postoperative day was similar in both groups; 11.5 g/dl in the current series compared to 11.1 g/dl in the 1982 series.