To investigate bladder neck and urethral function after radical hysterectomy, 21 patients were investigated before and 3 months after the operation. Each patient had an excretory urogram, CO2 cystoscopy, uroflowmetry, water cystometry and a urethral pressure profile, using a dual sensor microtransducer catheter, at rest and during stress. Postoperatively there was a significant reduction in urethral length and urethral closure pressure; however, pressure transmission ratios were maintained, indicating no loss of bladder neck support with stress. Of the six patients with pre-operative bladder neck weakness, two (33%) had stress urinary incontinence at the 3 months assessment. No patient with a normal pre-operative assessment developed this complication. Fifteen (71%) voided by abdominal straining and this manoeuvre emptied the bladder effectively. These data suggest that patients with pre-operative evidence of an incompetent bladder neck may be predisposed to develop stress urinary incontinence after radical hysterectomy because of a reduction in the urethral closure pressure.