Ureteral endometriosis is the involvement of ureter by endometriotic tissue. There are two types of this condition: intrinsic and extrinsic. Intrinsic ureteral endometriosis is histologically defined by infiltration of the muscularis of the ureteral wall. Extrinsic involvement is more common (80% of cases) and is caused by progressive enclosure of the ureter by endometriotic tissue. Thus, ureteral endometriosis should be considered in any female patient of child-bearing age who has obstructive uropathy attributable to extrinsic obstruction of the distal ureter.