The undertaking of the treatment of an infant born with bladder exstrophy is one of the most weighty responsibilities that can fall upon the shoulders of the reconstructive sur geon. The modern treatment of a child born with bladder exstrophy began in the mid- 1970's with the widespread application of staged reconstruction. This approach has consistently yielded very good results in several series. However, as in all serious congeni tal birth defects, there is certainly room for advancement. Issues such as the routine use of osteotomy, timing and type of epispadias repair, combining bladder closure with epispadias repair, the approach to the small bladder, and the management of a failed exstrophy still remain. This National Institute of Health/Na tional Kidney Foundation/Johns Hopkins-sponsored seminar was an attempt to bring ex perts in the field of pediatric orthopedic surgery, pediatric urology, pediatric surgery, adult urology, and basic science together to share their experiences in an attempt to foster new clinical and basic science research communications between the participants. If these col laborations result, then this first international meeting will have been successful. The editors would like to thank all of the contributors for their timely and complete submissions. John P. Gearhart, M.D. Ranjiv Mathews, M.D. vii CONTENTS 1. The Embryology and Epidemiology of Bladder Exstrophy ................. .