One hundred sixteen patients with "single ventricle" underwent 147 operations between 1967 and July 1982, with an actuarial survival rate (hospital deaths are included in all actuarials) at 10 years of 66%. One hospital death (2%) occurred after 45 primary "classic" shunting operations, and the 10-year actuarial survival was 85%. There were no hospital deaths after atrial septectomy or pulmonary artery banding, and the 10-year actuarial survival rate after these as initial procedures was 76% and 74%, respectively. Thirteen of 36 patients (36%) who underwent ventricular septation between 1967 and November 1, 1983, died in hospital. Among the 13 with the ideal morphologic characteristics of double inlet left ventricle without major associated cardiac anomalies, and without the need for valve replacement or a valved extracardiac conduit, there were no hospital deaths and a late survival rate of 77% (confidence limits 59 to 90%). Sixteen of 73 patients (22%), including those with tricuspid atresia, undergoing the Fontan-type procedure between 1967 and November 1, 1983, died in hospital. Multivariate analysis indicates that cardiac morphologic patterns other than tricuspid atresia are risk factors for hospital death in this group. The 10-year actuarial survival rate among the 73 patients was 71%, but only 1 death (associated with reoperation) occurred more than 2 months after operation. Ninety-seven percent of all surviving patients are in New York Heart Association functional class I or II, as are 100% of those who underwent septation and 96% of those who underwent the Fontan-type procedure.