The insertion of a double J catheter (DJ) has widespread, becoming a usual procedure and standard of care in urology. Despite its relative simplicity it is not free from intraoperative risks or problems during the weeks after the implant. Conversely, despite great advances in design of these catheters the ideal material has not been discovered yet, one that is perfectly biocompatible with urine and avoids completely the advent of complications. The range of problems associated with DJs is variable: from mild self-limited dysuria or hematuria to more complex situations with higher risk, such as catheter migration, complete calcification, breakage, obstruction and renal unit loss. The treatment of theses complications must combine maximal efficacy for their resolution with the least possible surgical aggression. Accordingly, the different options of endourological approach become very important and they are the cornerstone for the treatment of the complications associated with ureteral catheters. The objective of this review is to present the main complications derived from the insertion of a DJ, their diagnosis, prevention and treatment, focusing mainly in the different endourological techniques.