The mortality rate from congenital diaphragmatic hernia is not much better than it was 25 years ago. Most children, who are more than 24 hours of age at operation, survive. On the first day of life postoperative mortality is about 47%. Pediatric surgical problems are stabilization of the diaphragm and abdominal decompression. Some risk patients may be brought out of the fatal zone by high frequency ventilatory support and pharmacologic reversal of the fetal circulation. The most important causes of death are pulmonary hypoplasia with abnormal pulmonary vascular reactivity and persistent fetal circulation, iatrogenic pneumothorax, interstitial emphysema, mediastinal shifting with subsequent pulmonary hypertension and right to left shunting, and associated cardiac malformations.