Thirty three femoropopliteal and infrapopliteal artery bypass grafts with in-situ saphenous vein as a conduit, operated and followed during 42 months are described. This method involved the use of microscissors and valvulotome (Leather) and of a modified valve cutter (Hall) to render the vein insufficient through the intraluminal incision of its valves, transversally to the cusps axis. Arteriovenous fistulae were detected intraoperatively visually and by angiography, and ligated. The operative indications were rest pain; ischemic ulcers and distal gangrene in 79% of cases, and invalidating claudication in the rest. The vein utilization rate was 97%. The cumulative patency rate for all grafts was 97% at 3 months, 82% at one year, 78% at two years and 75% at three and a half years. At 42 months, 4 of 18 femoropopliteal bypass grafts had occluded, with a cumulative patency rate of 78%. In the same period, 4 of 15 tibial or peroneal bypasses had occluded, with a patency rate of 72%. The data presented suggests that in Chile this technique should be preferentially adopted to revascularize the lower extremity, particularly in distal artery bypass grafts, due to the superior capacity of the in-situ saphenous vein to remain patent in low-flow states with poor outflow tracts.