A 12-year-old boy with tetralogy of Fallot was evaluated for increasing cyanosis and exercise intolerance. The patient had a right Blalock-Taussig shunt operation 11 years previously and a left modified Blalock-Taussig shunt operation one year previously. After demonstration of hypoplastic pulmonary arteries, the stenosed right Blalock-Taussig shunt and the totally occluded, left modified Blalock-Taussig shunt were successfully dilated with a 7-mm-diameter angioplasty balloon resulting in a 5-mm-diameter patent shunt. We believe that, when possible, balloon dilatation angioplasty of stenosed Blalock-Taussig shunts is a reasonable and safe alternative to surgery.