Independent of cause, when any part of the urinary collecting system—the ureter, bladder, or urethra— is permanently unable to take part in the transport of urine from the body, diversion of the urinary flow is necessary. Various procedures have been devised to accomplish this, including implantation of the ureters into the bladder, the sigmoid colon, or a loop of terminal ileum. This last procedure, the establishment of an ileal conduit (Fig. 1), is generally recognized to be the most effective (3, 11, 14–16). Since this operation was first performed fourteen years ago (1), many studies have been made to determine the incidence and nature of resultant electrolyte imbalance and of such complications as pyelonephritis and hydronephrosis (2, 4, 5, 9–11, 16, 19). Few have made definitive investigation, however, into the emptying mechanism of the conduit, or, in fact, have indicated whether stasis of urine might be a significant problem. During 1964 a cinefluorographic study was made to determine the functional characteristics of the ureters and ileal conduits after this diversionary procedure. Material and Methods Material: Thirty-five patients were studied. The average age was twenty-four, with a range of two to sixty-five years. All were examined by the method of retrograde cinefluorography to be described, and 10 of them who were considered to have satisfactory renal function were examined by intravenous urography also, with cinefluorographic study of the pelvis, ureters, and conduit. Ureteral transplantation had been performed in most instances because of a congenital or neoplastic lesion (Table I). Retrograde Cinefluorography: A retention catheter was inflated just inside the ileal stoma, and a sample of urine collected for bacterial culture. The patient was placed in the supine right oblique position under fluoroscopic control. Renografin-60 (methylglucamine diatrizoate), in sufficient amount to produce bilateral ureteral reflux, flowed into the loop by gravity feed from a bulb syringe placed 10 inches above the ileal stoma. The conduit and ureters were viewed cinefluorographically, with the retention catheter in position and again after its removal. The patient was then placed in the erect position and further observations were made. The effect of contraction and relaxation of abdominal muscles was studied by cinefluorography while the subject was supine and erect. Results The only difference in results obtained by the two investigative methods lay in the density of contrast medium, which was poorer in the intravenous studies. Dynamics were identical by both methods. The erect position aided dramatically in drainage from the pelvis and ureters into the conduit, but in only 5 cases did it appear to increase drainage to the exterior. A consistent finding in all cases in which any degree of peristalsis was observed was a complete lack of co-ordination between contraction of the ureters and of the conduit: we consider this very important.