In 114 out of 1215 stress-incontinent women the maximal urethral closure pressure was determined. Descensus of urinary bladder and urethra was proved by lateral urethrocystography. In the group of sphincter weakness (Edwards) which was to be found in 46 patients, only 48% became continent after colporrhaphy, Marshall-Marchetti-Krantz or sling surgery. If the pressure profile was found to be normal 74% of our patients felt cured after incontinence-operation. Sphincter weakness determines a failure due to surgery which is statistically of significance (P less than 0,01).