Introduction: Endometriosis is common in women of reproductive age with an incidence of 15%. Ureteral endometriosis is a rare (1%-5%) form of urinary tract endometriosis. Case history: A 42-year-old nulliparous woman attended to her general practitioner for severe headache, vague back pain, nausea and vomiting. Investigations revealed high blood pressure, serum creatinine 3,5mmol/l, normal blood count. Abdominal ultrasound and MRI showed bilateral hydronephrosis with dilated ureters. A double J ureteric catheter was placed on right kidney and a nephrostomy on the left. Gynaecologic consultation was undertaken with the only finding being a slight non-tender non-nodular thickening of the left paracervical tissues. Normal tumor markers. Patient underwent an exploratory laparotomy by a multidisciplinary team. Intraoperatively, no ovarian endometrioma or other lesion was identified. Both ureters were dilated with thick muscular wall. Dissection of the ureteral canal after mobilization of the bladder revealed a thick fibrous tissue at the level of the uterosacral ligaments, which completely encased the ureters. Both ureters were cut below the pelvic brim at the level of the fibrous tissue and were reimplanted in the bladder with a bladder hitch procedure over double J ureteric catheter. Uneventful post-operative course. Histology confirmed the presence of endometriosis on the peritoneal tissue that was removed. Discussion: Ureteral endometriosis can present with non-specific symptoms for example dysmenorrhea, dyspareunia, pelvic pain, infertility, altered urinary function and rarely haematuria. Progressive obstruction of the ureters may ultimately lead to hypertension and acute renal failure. Ureteral obstruction is mostly associated with an endometriotic nodule. In our case, the presence of thick fibrotic peritoneal tissue surrounding the ureters was probably the mechanism that led to ureteric dilatation. Surgical management aims to free the ureter from all endometriotic tissue, and restore normal function.