Arterial switch operation is the intervention of choice in neonatal period in the case of transposition of the great arteries. In patients who have passed this period for various reasons and therefore having a low left ventricular pressure, two stage surgical intervention offers a chance of arterial switch procedure for them again. In our institute, between June 1990 and October 1996 among 84 patients who have had arterial switch operation for transposition of the great arteries +ventricular septal defect (or Taussig-Bing) patients had two stage intervention to regain the change of anatomic correction (4 to 40 weeks old, mean 21.2±11.6). For the first stage procedure seven patients had modified Blalock-Taussig shunt and pulmonary artery banding, one patient having a large patent ductus arteriosus and another patient with aortopulmonary collaterals had only pulmonary artery banding, and one patient having subpulmonic dynamic stenosis had only modified Blalock-Taussig shunt operation. Serial echocardiographic studies have been performed 48 hourly in the postoperative period; rightward convergence of the interventricular septum giving left ventricle a spherical shape and synergetic contractions of the left ventricle posterior wall with the septum are accepted as the main criteria in the determination of the availability of the left ventricle for arterial switch operation. At the same time, it is preferred that the ejection fraction and the shortening fraction should be in the normal values and the left ventricle posterior wall thickness should be at least 4 mm. According to these criterias, the time elapsed for the left ventircular availability to the second stage varied from 4 to 15 days (mean 8.5±3.0). Arterial switch operation have been performed to the patients 2 to 32 weeks after the first stage, no mortality occurred and all of the patients were hemodynamically stable after the second stage operation. In 4 patients who had delayed second stage operation (between 16-32 weeks), two had mild and one had mild to moderate aortic insufficiency. Postoperative left ventricular function was followed up to 2 to 17 months (mean 7.7±5.54) and revealed no significant difference compared to the patients having the arterial switch operation in single stage. According to these findings, two-stage intervention seems to be the procedure of choice in patients who have passed the neonatal period (preferably before the 6th month) to avoid from the expected complications of the atrial switch operations.