From 1982 to 1987, 38 consecutive patients with pulmonary atresia and ventricular septal defect underwent staged unifocalization procedures in preparation for final intracardiac repair of the anomaly. Thirty-six patients had concordant visceroatrial, atrioventricular, and ventriculoarterial connections. A central pulmonary artery confluence was present in 19 patients and absent in the remaining group. All patients with central pulmonary arteries had inadequate peripheral pulmonary arterial arborization. Systemic collateral arteries were present in all 38 patients. The objectives of the unifocalization procedures were the interruption of extracardiac sources of pulmonary arterial blood flow, the restoration of segmental, lobar, and pulmonary arterial confluence, the replacement of missing central pulmonary arterial branches, and the creation of a central, accessible source of pulmonary arterial blood flow. A total of 54 unifocalization procedures were performed in the 38 patients. These procedures included 85 permanent connecting anastomoses, 15 temporary anastomoses to the ascending aorta, 13 angioplasty procedures, and 15 modified Blalock-Taussig shunts. Three patients died after unifocalization (two early and one late). By the end of the study, eight patients were still waiting for further unifocalization procedures or angiographic assessment. Four patients were rejected for further surgical treatment because of persistent, uncorrectable defects of the pulmonary arterial arborization pattern. Twenty-three patients underwent complete intracardiac repair with two deaths (one early and one late). Postrepair, intraoperative right ventricular/left ventricular systolic pressure ratio after complete surgical repair ranged from 0.4 to 1.0 (mean = 0.63, standard deviation = 0.14). At the end of follow-up, 21 survivors of complete repair were free of significant symptoms. Unifocalization procedures designed to improve the pulmonary arterial arborization pattern of patients with pulmonary atresia and ventricular septal defect with or without central pulmonary arteries can prepare a significant number of these patients for successful intracardiac repair of the anomaly.