The Fontain principle of redirecting systemic venous blood into the pulmonary arteries via a conduit has gained a much wider application than initially intended. This operation was applied in 15 patients, 5 of whom had classical tricuspid atresia with concordant arterial connections. The other 10 patients showed a variety of congenital malformations, such as double-inlet univentricular heart with discordant arterial connections, double-outlet right ventricle with common atrioventricular canal, Ebstein''s anomaly with almost imperforate tricuspid valve, hypoplasia of right ventricular inflow and a crisscross heart with straddling right atrioventricular valve. Important associated anomalies, such as common atrium and anomalous pulmonary and/or systemic drainage, required particular adaptation of the technique. Of the 15 patients 13 survived operation and are presently alive. One death occurred in a patient in whom the preoperative diagnosis was adjusted during operation because of unexpected total anomalous pulmonary venous connections. The other death occurred in a patient suffering from the asplenic syndrome. The autopsy in this patient suggested that the large baffle used for atrial septation and ventricular exclusion had obstructed pulmonary venous return. Fontain''s operation has a place in the treatment of otherwise anatomically uncorrectable lesions.