Twelve patients with uncomplicated transposition of the great arteries were operated upon in the first month of life following an initial Rashkind procedure. They were all in a clinically unacceptable condition and were mostly acidotic or bad mixers without acidosis. Two patients died postoperatively from a cerebral haemorrhage not discovered prior to operation. One patient died 5 months postoperatively from bronchiolitis. At postoperative follow-up, all patients were asymptomatic. Cardiac catheterization showed that 1 patient had a significant upper caval vein stenosis, 2 patients had small atrial shunts, and 1 patient had an unimportant pulmonary stenosis. Innocent atrial rhythm disturbances were encountered in 1 case only, whereas 9 patients had normal sinus rhythm at the last examination. The Senning operation remains a good alternative for transposition repair in the neonate.