An apparatus for controlling flow of urine in a patient suffering from urinary incontinence comprises an implantable constriction device for gently constricting (i.e. without substantially hampering the blood circulation in the tissue wall of the urethra, ureter, renal pelvis or bladder) at least one portion of the tissue wall of the urethra, ureter, renal pelvis or bladder to influence the flow of urine, and a stimulation device for stimulating the wall portion of the tissue wall. A control device controls the stimulation device to stimulate the wall portion, as the constriction device constricts the wall portion, to cause contraction of the wall portion constricted by the constriction device to further influence the flow of urine. The apparatus can be used for restricting or stopping the flow of urine, or for actively moving the urine in the urinary passageway, with a low risk of injuring the urethra, ureter, renal pelvis or bladder.