An increasing number of very old patients are treated in hospitals but there are few Swedish studies of the results of the treatment. In this study the results and costs of vascular surgery in octogenarians were compared to those of younger patients. All Swedish patients treated in 1996 (10,185 procedures) were analyzed; one fifth were over 80 years of age. During the past ten years the number of procedures had increased 2.6 times in the old age group. The technical result, measured as patency rate one year after bypass surgery, was comparable in the two groups--73 per cent versus 81 per cent--but the mortality was higher in the older age group both in direct connection with the procedure and a year thereafter. The cost per procedure was not higher in the old age group.