Construction of a neobladder utilizing intestine is currently considered to be the ideal option for the cystectomized patient. We reviewed the history as well as the physical and urodynamic principles of the substitution neobladders and continent reservoirs. In our series of patients who underwent cystectomy from January 1988 to December 1991, we have performed bladder substitution using detubularized ileum in 37 patients (18 Camey II and 16 Hautmann) and 13 patients had a continent reservoir (Mainz pouch). Patient ages ranged from 33 to 72 years (mean 60.4). The functional behaviour of the intestinal neobladders was analyzed clinically, radiologically and urodynamically. Eleven of the 18 patients with a Camey II (61.8%) and 3 of the 16 with a Hautmann (18.7%) neobladder were incontinent during the night, the difference being statistically significant (p < 0.05). Incontinence correlated manometrically with high pressure peaks in the Camey II neobladders and waves with a lower intensity were recorded in the Hautmann neobladders. Flowmetry revealed a normal peak flow in all but one Camey II that required internal urethrotomy due to urethroileal stenosis. The maximum capacity was 215-500 cc for the Camey II (mean 340 cc), 310-850 cc for the Hautmann (mean 590 cc) and 350-925 cc (mean 675) for the Mainz pouch. Intermittent catheterization was required in 3 of the Camey II and 1 of the Hautmann neobladder with important postmicturition residual urine. The patients who received the Mainz pouch had good continence, with pressure recordings less than 55 cm H2O), which is lower than the continent closing pressure. Only one case was incontinent due to failure of the intussusception mechanism. The good functional results achieved with the Hautmann procedure are underscored. The pressure recordings and the incidence of night incontinence for the foregoing procedure were lower than the Camey II. For the unviable urethra, the Mainz pouch achieves moderate pressures and is socially acceptable.