Two-dimensional endoluminal sonographic imaging of the ureter demonstrates the periureteral anatomy, as well as define lesions within the ureteral wall. It has been used for evaluation of a wide range of abnormalities, including ureteropelvic junction (UPJ) obstructions, crossing vasculature at an obstructed UPJ, ureteral and renal pelvic neoplasms, and the obstructed ureter. Three-dimensional (3D) reconstruction of two-dimensional (2D) sonographic imaging is a new technique applicable to intraluminal imaging. It offers advantages over 2D imaging by demonstrating the spatial relation of anatomic structures that cannot be appreciated using conventional imaging. We have evaluated a number of ureters with various pathology using 2D endouminal sonography. In this paper, we present three cases in which we have used 3D reconstruction to gain a clearer understanding of the pathology. Although still early in its application, 3D endoluminal reconstruction has potential to be a clinically useful aid to surgical decision-making.