Objective: Urinary incontinence following radical prostatectomy is thought to be mainly due to stress leak as a result of sphincter insufficiency or detrusor dysfunction. However, a number of patients complain of stress–independent urinary leakage following voiding, i.e. a post–micturition dribble, of uncertain origin. In order to establish wether post–micturition dribble is related to altered post–void milking in the urethra, voiding cystourethrograms (VCUGs) were performed before and after radical prostatectomy and correlated with the presence of post–micturition dribble.Methods: 23 VCUGs were recorded before and 19 VCUGs at 10–15 days following radical prostatectomy. A standard questionnaire regarding urinary symptoms was given to all patients pre– and postoperatively at defined intervals.Results: 12 of 19 patients (63%) had post–void urethral milking prior to surgery, none of these reported post–micturition dribble. 6 of the 7 patients (86%) without post–void urethral milking reported post–micturition dribble. Postoperatively only 1 of 16 patients (6%) had post–void urethral milking. Of the 15 patients without postoperative urethral milking, 13 (87%) reported post–micturition dribble. The decrease in rate of milking and increase in rate of post–micturition dribble from before to after surgery was statistically significant (χ<sup>2</sup> test, p = 0.0001 and p<0.0001, respectively.Conclusions: These data suggest that post–void milk–out of the urethra is often absent in the early postoperative period after radical prostatectomy and that this is associated with post–micturition dribble. Aside from detrusor and sphincter dysfunction, urethral dysfunction, i.e. the absence of urethral post–void milking, seems to be an additional cause of incontinence following radical prostatectomy.