HAVING in mind the large number of serious accidents which are associated with fast transportation and large scale heavy industrial activity, one would expect to see a considerable number of diaphragmatic hernias along with the abdominal traumas, fractures of the pelvis, spine and ribs and other injuries involving the trunk. Actually, such is not the case, and a review of the surgical experience with hernia of the diaphragm at the Henry Ford Hospital during the past ten years has revealed that acute traumatic hernia of the diaphragm has been diagnosed only three times. During the same period, 206 fractures of the pelvis were indexed. The obvious conclusion is that the diaphragm is a hardy structure which is remarkably resistant to disruption. The three acute hernias were repaired immediately, but not before one of them became complicated with a perforation of the incarcerated stomach. Although it would appear that the logical