Mentor electronic bladder stimulators were implanted in 8 children with myelomeningocele who were being managed successfully with intermittent catheterization. Satisfactory clinical performance was obtained in only 3 of these children. In the 5 failures urine flow was sporadic and unreliable. In 6 patients electrode lead wires broke where they entered the anterior abdominal fascia. None of the 8 units functioned more than 29 months. Many technical problems must be resolved before bladder stimulators will have a significant role in the management of children with myelomeningocele.