This study reviewed 57 patients with 71 vascular occlusions treated with urokinase from 1985 to 1988. Of these patients, 89% were candidates for urgent surgery. Total clot lysis was achieved in 73% of cases. The success rate rose with increasing experience (p<0.05), and recent occlusions had more favorable outcomes than older ones (p<0.05). The length and type of occluded conduit (graft or vessel), age, sex, other medical conditions, and concurrent use of heparin had no influence on success. Of 18 cases successfully lysed and not subjected to any adjunctive therapy directed that the cause of occlusion, 9 (50%) reoccluded within 1 to 88 days (means: 25 days). Cases successfully treated with thrombolysis and surgery or dilation of the causative stenosis had poor 1-year patencies: 17%, 20%, and 55% for vein grafts, prosthetic grafts, and native arteries, respectively. With additional urokinase treatments, surgical operations, and percutaneous procedures, 1-year patencies were 22%, 45%, and 65%, respectively. © 1990 Reed Publishing USA.