Gunshot wounds of the chest are a common problem of the military surgeon in active warfare, but they are frequently seen also in civil practice in large municipal hospitals. The same principles of therapy apply in both instances, but certain differences are at once apparent. During warfare, more emergency operations are performed; the septic complications are more frequent, and the mortality rate is somewhat greater. In civil practice, gunshot wounds are usually small; there is only a small amount of tissue damage; septic complications are uncommon; recovery is prompt, and the mortality rate is low provided the great vessels are not penetrated (if they are, rapid or immediate death is the rule). These differences are due largely to the penetrating missile. Penetration of the thorax as seen in patients admitted to large municipal hospitals is usually caused by plain or jacketed bullets. In warfare, on the other hand, penetration is