A new technique is described to avoid kinking and improve flow in the ipsilateral subclavian-to-pulmonary artery shunt. Experience with this procedure is reviewed in 35 infants and children with a variety of cyanotic congenital heart disease, including 10 with tricuspid atresia. Of these, 17 had had previous shunts: a Waterston shunt in six, a Glenn shunt in six, and a contralateral Blalock-Taussig shunt in five. The mean age was 5.6 years (range, 1 day to 16 years), and the mean follow-up was 24 months (range, 11 months to 4.5 years). There were no early deaths (less than 30 days), but there were two late deaths. There were three shunt failures at 2 weeks, 1 month, and 10 months; two of the failures were in infants aged 1 day and 4 days at operation. There were no late shunt failures. The patency by the life table method was 91.4% at 6 months, 88.5% at 1 year, with no further drop-off. It is concluded that subclavian arterioplasty can be performed safely and offers improved shunt patency in comparing to the ipsilateral Blalock-Taussig shunt.