OBJECTIVE Creation of a 1-way catheterizable valve has resulted in dryness for a large group of children with intractable urinary incontinence. We document the incidence, time course and management of catheterization problems in 49 children who underwent urethral lengthening and reimplantation for intractable incontinence. METHODS We reviewed the records of 21 boys and 28 girls who underwent urethral lengthening and reimplantation between 1982 and 1995. Catheterization problems were defined as the inability of the patient or a family member to pass the catheter, and divided into early only, late only, recurrent and persistent problems. RESULTS Of the 49 patients 46 had neurogenic incontinence secondary to myelomeningocele and 35 (72%) never had difficulty catheterizing. Of the 14 children (28%) who had difficulty 7 (50%) were boys and 7 (50%) were girls. Two children (4%) with early only difficult catheterization have had no further difficulties during the last 14 and 6 years, respectively. In 3 children (6%) late only difficult catheterization began 17, 24 and 35 months, respectively, after the original bladder neck surgery. These problems were solved by changing to a Coudé catheter and/or avoiding over distension. The 7 patients (14%) with recurrent catheterization problems, some with long intervals between episodes, now catheterize easily. The 2 children (4%) with persistent problems required alternate access to the bladder. CONCLUSIONS The majority of children (72%) who undergo urethral lengthening and reimplantation never have any difficulty catheterizing. Those in whom difficult catheterization develops can be treated with minimally invasive methods without compromising the goals of the original surgery.