One hundred thirty-four cases of classical bladder exstrophy, managed at our institution, were reviewed. Fifty-six percent of the boys and 15% of the girls developed inguinal hernias over an average follow-up time-span of 10 years. Thirty-one percent of the patients with hernias underwent repair at the time of initial bladder closure. Forty-six percent of the patients who developed a hernia were diagnosed during the first year following their initial procedure. More than 50% of the individuals in the latter category presented with an incarcerated hernia, and required emergent management. Boys managed by staged reconstruction had a statistically significant risk of developing an inguinal hernia (P less than .001) compared with boys undergoing primary cystectomy and diversion. We believe the increased incidence of herniation with this congenital anomaly is secondary to a lack of obliquity of the inguinal canal, due to pubic diastasis along with an increased elevation of intraabdominal pressure following initial closure of the abdominal wall and bladder plate. To decrease the attendant morbidity of incarcerated hernias in this population, we stress the need for careful physical examination of the inguinal region and spermatic cord prior to surgery, along with repair of the patent processus vaginalis at the time of initial repair.