Early correction of congenital cardiac defects has been facilitated by the use of deep hypothermia and cardiocirculatory arrest. The technique currently used by us consists of surface cooling to 24 degrees C, total hemodilution, cardiopulmonary bypass to 20 degrees C and complete cardiocirculatory arrest. Rewarming is achieved with a pump oxygenator. In over 266 small children, 67% of whom were in the first year of life, lesions corrected included transposition of the great arteries (TGA)(43%), ventricular septal defect (16%), tetralogy of Fallot (16%), and total anomalous pulmonary venous drainage (5%). Early primary correction with deep hypothermia has a risk that is comparable to or better than staged repair.