The rate of postoperative infections in lower limb vascular surgery was first evaluated in a retrospective study of 416 bypass procedures (68 venous grafts and 348 prosthetic grafts) in 400 patients seen over a two-year period. 31 postoperative infections (7.4%) were found. Outcome was fatal in three cases. 70% of cases were due to a methicillin-susceptible Staphylococcus aureus. Antibiotic prophylaxis with oxacillin given during surgery and for the first 48 postoperative hours was used for the next 112 procedures (17 venous grafts and 95 prosthetic grafts) in 107 patients. The preliminary results show a fall in the rate of postoperative infection, with only 5 cases (4.4%). The only case due to a methicillin-susceptible Staphylococcus occurred after a second surgical procedure without antibiotic prophylaxis. These preliminary results are promising although the difference does not reach statistical significance. However, it is of note that no patient undergoing vascular surgery for the first time developed postoperative infection. Further prospective studies are needed to determine the optimal antibiotic prophylaxis in lower limb vascular surgery.