Sacrococcygeal teratomas (SCT) are the most common neoplasms in newborns with a reported occurrence of 1 in 35,000 live births. Highly vascularized tumors in which the ratio of tumor weight to patient weight approaches 1:1 are frequently associated with hyperdynamic states, prenatal hydrops, placentamegaly, postnatal high-output cardiac failure, and carry a high perinatal mortality rate. Operative management of giant, highly-vascular sacrococcygeal teratomas in neonates can be complicated by life-threatening hemorrhage. Laparotomy, control of the aorta, and the arterial blood supply to these tumors before resection has been advocated as a safer alternative. The authors report their experience with three infants successfully treated using this approach. Hemodynamic stability was maintained during the operations. All tumors were resected successfully. The patients are alive without evidence of recurrence, 8.5 months to 18 months (average, 14.3 months) after the operation. Alpha-fetoprotein levels dropped to normal range after the removal of SCT and have remained normal in follow-up. Vascular control before excision of giant, highly-vascular SCT in neonates is safe, decreases intraoperative blood loss, and postoperative morbidity.