A technique of placement of central venous catheters for hyperalimentation, long term antibiotic treatment or chemotherapy by cut-down and positioning of the catheter tip with intravascular electrocardiography is described. The method was used in 384 patients during a period of four years. The patients varied from premature newborns to adolescents. The external jugular vein was used in 218 patients, the internal jugular vein in 150, the cephalic vein in 11 and the axillary vein in five. Catheters were successfully positioned by electrocardiogram (ECG) control in 95 percent of the patients. In only 5 percent of the patients, the ECG was difficult to interpret because of interference, poor electrode contact or unsatisfactory ECG image or tracing. Roentgenograms to check catheter location did not have to be done in the operating room. Confirmation of catheter position was done in the recovery room or on return to the neonatal intensive care unit. Using the cut-down procedure described, there were no complications, such as bleeding or chest wall infections, along the course of the catheter.