Our incidence of urological complications in 860 consecutive renal transplants is 3.4 per cent. A further reduction in incidence is demonstrated in the most recent 250 transplants of this series. Urological complications have been kept to a minimum by strict adherence to certain principles in donor nephrectomy, management of multiple and small arteries, and the technique of graft implantation.When urological complications were suspected early and judicious use of 131I hippurate scintiphotographic techniques has proved to be the most helpful method to evaluate patients. If a urological complication did occur prompt recognition and treatment were responsible for a high rate of graft salvage, low incidence of sepsis and absence of patient mortality.