The target population of this study is children with primary or secondary daytime urinary incontinence, who have failed to improve adequately despite compliance with at least 6 months of standard medical therapy. These children will have abnormal urodynamics, a normal bladder ultrasound and an MR imaging showing that the conus medullaris of the spinal cord is at a normal position and that there is no other significant dysraphic lesion present. The entry criteria are designed to separate this very specific subset of patients from the much larger, more general group of children presenting for evaluation and management of incontinence.