Since April 1975 we used 50 bovine arterial heterografts for reconstructive surgery after chronic arterial occlusions or for the production of AV-shunts needed for chronic dialysis. In none of the cases incompatibility was seen. The early results (with a follow-up period of 6-10 months) after femoro-popliteal bypass were excellent, as far as a good peripheral run off was present. Several shunts (n = 7) containing 2-3 transplants, are still functioning 3-10 months after implantation. At present, we use bovine transplants in reconstructive vessel surgery when a thrombendarterectomy or the connection of venous grafts is impossible or when the operative procedure should be kept short in high-risk patients. To produce AV-shunts in patients with renal insufficiency we prefer this type of grafts when all conventional techniques were already used.