Between 1983 and 1994, 515 pediatric patients with medical and/or surgical problems underwent urodynamic evaluation. We present the urodynamic findings of 214 children with surgical pathology: 73 cases with vesicoureteral reflux, 26 with urethral stricture, 11 with posterior urethral valves and 104 cases with lipo- and myelomeningocele. We found a high incidence of urodynamic abnormalities associated to these pathologies: 46.5 in patients with vesicoureteral reflux, 88.4% in urethral strictures, 54.4% in posterior urethral valves and 100% in patients with spina bifida. In our opinion, the urodynamic assessment has a contributory role in the indication for corrective surgery; because the knowledge of the vesicourethral complex state will help to stabilize it through a correct individualized medical treatment before surgical treatment, delaying or even avoiding surgery in some cases.