Thirty-three patients underwent percutaneous treatment for upper urinary obstructive disease in our Institute. Cold-knife incision of 16 cases of uretero-pelvic junction obstruction and 4 cases of infundibular stenosis was performed. Balloon dilatation of the caliceal neck was performed in 1 patient with caliceal diverticulum. In 4 of the patients treatment failed requiring open surgical correction. Thirteen patients presented iatrogenic ureteral obstruction: balloon dilatations or cold-knife incisions were performed. Four of the 9 patients evaluable obtained significant benefit from the endourological treatment. Endopyelotomies for UPJ obstruction seem effective and reduce morbidity and operating times. Ureteral obstructions appear less responsive to the endo-urological approach. Definitive conclusions concerning the effectiveness of these procedures requires larger series of patients and longer follow-up.