Thirty-seven infants with total anomalous pulmonary venous drainage have been operated upon at The Hospital for Sick Children, Great Ormond Street, London, with 13 survivors. Most were rapidly deteriorating when admitted. Cardiac catheterization, angiography, and operation were urgently undertaken to achieve the maximum salvage. Physical examination, plain radiography, and electrocardiography were insufficient for accurate diagnosis. Survival was closely related to the degree of pulmonary hypertension, which was dependent on the type of anomalous venous drainage and the presence of pulmonary venous obstruction. The prognosis was good for patients over 3 months of age, especially those without pulmonary venous obstruction, provided that they arrived in the hospital in reasonable condition. The best survival rate, nine of 11 cases, was achieved in those patients between 3 and 12 months of age with supracardiac drainage.