The authors applied a new method, the low pressure ureterosigmoidostomy, namely the Mainz pouch II. The essence of the operation was a reverse "U" shape opening of the sigma, detubularization, then suturing together, so a diverticulum like cavity was created, and the ureters were implanted here. The detubularization broke the peristaltic pressure wave in the bowel and protected the kidneys from reflux, inflammation and stone formation. From early complications the suture insufficiency and sterile disruption of the abdominal wall emerged. The former was solved with conversion to rectal bladder, the latter with special stitches. Hyperchloraemic acidosis manifested in every case and it was compensated with medicines. For the 23 tumour free patients the operation brought daytime continency, a good quality of life, and as a palliation diminished the complaints. There were no inflammatory complications and only one ureter stricture and one fistula developed. The operation technically was simple and united the advantages of the ureterosigmoidostomy and the low pressure reservoir.