Twenty-eight cases of infradiaphragmatic total anomalous pulmonary venous return are presented, 17 without associated complex intracardiac anomalies (group A), and 11 with additional complex lesions (group B). The anomalous site of connection was to the portal vein in 19 cases (68%), to the inferior vena cava in 4 (14%), the ductus venosus in 2 (7%), to the left hepatic vein in 2 (7%), and unknown in one. A patent foramen ovale was present in 82 per cent of cases in group A and 40 per cent in group B and was frequently associated with a small left atrium and left ventricle. Nine cases (8 in group A; 1 in group B) had surgical correction, with 3 long-term survivors. The surgical mortality was 66 per cent. The postoperative haemodynamic status of the 3 surviving patients is very satisfactory, though 1 had a residual atrial septal defect. Factors which adversely affected the surgical outcome were: (1) a critically ill infant, (2) small left atrium and left ventricle, (3) a patent foramen ovale rather than atrial septal defect, (4) systemic arterial oxygen saturation less than 70 per cent, and (5) pulmonary arterial pressure in excess of systemic arterial pressure. The mortality for the entire series was 93 per cent.