More than 200 years ago William Hunter described the first arteriovenous fistula (a.v.). Fragments of low velocity are the most frequent cause for a combined vascular trauma. However, a.v. fistulas may also develop after a skull fracture, after surgical interventions (lumbar disc operation, suture ligation for the removal of an organ like the kidney, the spleen and others). Three circulatory disorders may follow an a.v. fistula. Local signs at the location of trauma (machinery murmur, varicose veins). Cardiac dilatation due to the increase of heart volume. Degenerative changes and aneurysm formation in the artery above the fistula. Late complications may arise in the dilated central segment of the artery (aneurysm or thrombosis). The etiology of 223 traumatic a.v. fistulas (1939-1973) were in the majority (82%) of patients caused by war time injuries. Fractures and stab wounds were also common causes of a.v. fistulas. The location of a.v. fistulas was in about 50% in the lower extremities and only in 3% in the trunk. As to therapy - in contrast to the older quadruple ligature - the separation method should be the method of choice. The repair in arterio-venous fistulas should be done as early as possible. The operative cure rate in our series was 96%.