A study was conducted in 24 patients to determine the usefulness of the intestinal segments used in bladder replacement surgery. Continence and voiding were analyzed, particularly the more important functional symptoms of the lower urinary tract and the urodynamic behaviour of the intestinal reservoirs/conduits. The Bricker ileal conduits (8 cases) showed poor accommodation during the filling phase, making its use as a reservoir little advisable. In general, bladder augmentation (9 cases) with intestinal segments were shown to be useful reservoirs, but of limited capacity for voiding. The ileal reservoirs (7 cases) used for bladder substitution had, in general, compensated voiding, but with defects in the filling phase.