Among 336 consecutive renal transplantations performed in our centre from March 1979 to December 1988, we have observed 26 cases of urinary leak in 25 patients. We have separated the ischemic and non-ischemic urinary leaks. The former (11 episodes) would have been prevented in most cases with better graft removal. The latter (15 episodes) were predominantly secondary to an anastomotic leak. We have treated surgically these urological complications. Only one patient died. The one-year graft survival rate was 67% in the 25 kidneys but the graft loss was directly due to the urinary leak in three cases.