The Society for Fetal Urology(SFU) hydronephrosis registry began enrolling patients as of 5/01/06. Currently, three centers have received Institutional Review Board(IRB) approval and are actively enrolling patients. The initial goal was to enroll 50 patients and present the status of the registry at the American Academy of Pediatrics Section on Urology meeting. The update of the first 63 patients was very well received and has created a considerable interest in the registry. Currently, 6 other centers are in the process of applying for IRB approval prior to their participation in the registry. In addition, the Coordinating Council for Registries as well as the executive committee for the AAP both have given their widespread support for the prenatal hydronephrosis registry. anthony.herndon@ccc.uab.edu