From 1978 through 1983, 206 patients had 236 polytetrafluoroethylene (PTFE) grafts inserted in vascular wounds. More than 85% of injuries were due to gunshot wounds, shotgun wounds, or stab wounds. Arterial grafts were inserted into vessels of the upper extremity (38.8%), lower extremity (46.1%), neck and chest (8.8%), and abdomen (6.3%). Grafts were most commonly placed in the brachial or superficial femoral arteries. Venous grafts were more commonly inserted into vessels of the extremities (96.7%), with the majority located in the superficial femoral vein. PTFE was found to be an acceptable prosthesis for interposition grafting in arterial wounds, but long-term patency was less than that seen when interposed saphenous vein grafts are used. Early and late occlusions were a significant problem with 4-mm PTFE grafts in the brachial artery, and this size is not recommended in this location. Peripheral PTFE graft infection did not occur in the absence of exposure of the graft or of osteomyelitis. Exposed grafts did not fare well and early coverage is recommended, even with extensive soft-tissue wounds around the graft. PTFE grafts inserted in proximal extremity veins are excellent temporary conduits which decrease hemorrhage in blast cavities and fasciotomy sites, but all grafts studied by venography at 7 to 14 days were either narrowed or occluded.