Surgical blood loss of >1000 mL or blood loss that requires a blood transfusion usually defines intraoperative hemorrhage. Intraoperative hemorrhage has been reported in 1% to 2% of hysterectomy studies. Cardiovascular instability with significant hypotension often results from a loss of 30% to 40% of the patient's blood volume and >40% blood loss is life threatening. Preparation, planning, and practicing for a massive hemorrhage is essential for all surgeons and gynecologic operating room teams. Emergency steps should be written and posted in the operating room and rehearsed quarterly.