Twelve patients with a double uterus, unilateral vaginal obstruction, and ipsilateral renal agenesis are described. The clinical presentation varies, depending on whether the obstruction was partial or complete. In rare instances a communication existed between the obstructed vaginal pouch and the opposite patent vagina through a defect in the septum of the double uterus. Early accurate diagnosis followed by the excision of the obstructing vaginal septum offers complete relief of symptoms while preserving reproductive capacity.