Ureteral stents are one of the most frequently used tools in urology. These medical devices have a multitude of both prophylactic and therapeutic indications. Among the first ones, the use of stents related to the treatment of ureteral or renal stones, in renal transplant surgery and in reconstructive surgery of the upper urinary tract by endourological, laparoscopic, robotic or conventional surgical approach. Therapeutic indications are related to urinary tract decompression in obstructive uropathy and as in the conservative treatment of upper urinary tract trauma.Although it has clear benefits, unfortunately it is not free of side effects. Complications associated with ureteral stents can be classified as intraoperative, early complications if they appear between 2 and 4 weeks after stenting, and late complications, depending on the time of onset of side effects. The most common side effects are the development of vesicoureteral reflux, LUTS and stent discomfort. The complications with the highest rate of incidence are asymptomatic bacteriuria and urinary tract infection. There are also common events related to ureteral stent dislodgement and crystallization of the stent surface resulting in encrustation.