Tracy CR, et al. - The authors herein, have drawn a comparison of intraoperative and postoperative outcomes and complications in the following 3 groups who underwent ureteroscopy for nephrolithiasis [no ureteral access sheath, 12/14 Fr and larger 14/16 Fr ureteral access sheaths (UAS)]. When compared to the 12/14 Fr UAS, the use of a 14/16 Fr UAS allowed a similar stone-free rate and improved operative efficiency with no increased risk of ureteral injury or post-operative complications