Successful long-term phrenic nerve pacing has been reported in adults with acquired central hypoventilation syndrome. This report summarizes our experience with phrenic nerve pacing in 3 infants with congenital central hypoventilation syndrome. The electrodes were implanted in the lower thoracic portion of each phrenic nerve. In all patients. bilateral simultaneous pacing was required to maintain an adequate arterial PO2, tidal volume, and minute ventilation during quiet sleep. Case 1 died of problems primarily related to the severe cor pulmonale that had been present before pacemaker insertion; at autopsy, the pacemaker system was intact and there were no significant phrenic nerve abnormalities. Case 2 later developed failure of awake ventilatory control and died because of extensive phrenic nerve damage incurred by 19 days of continuous pacing. Case 3 has received quiet sleep pacemaker support since September 1977 and has been able to maintain normal quiet sleep ventilation in this manner. Phrenic nerve pacing can be successful in infants as long as continuous pacing is not required. Bilateral simultaneous pacing appears to be an appropriate alternative to home-based intermittent positive-pressure breathing for long-term management of children with central hypoventilation syndrome.