BACKGROUND: The prevalence of bladder exstrophy (BE) and other rare congenital urologic disorders has declined significantly in the United States over the past 50 years. This creates a concerning scenario where the pool of adequately trained surgeons for rare but severe disease processes is vanishing, despite a large need internationally and future need domestically. We sought to identify the current case volumes among trainees and compare perceptions between fellows and program directors (PDs) regarding the number of cases needed for competency and proficiency. METHODS: We performed a retrospective analysis of pediatric urology fellow case logs to trend the incidence of complex pediatric cases in the US from 2010-2022. De-identified self-reported total case volumes were obtained from available Accreditation Council for Graduate Medical Education (ACGME) files for graduating National Pediatric Urology Fellows. We then performed a cross-sectional survey of current and recently graduated pediatric urology fellows and PDs regarding their perceptions of an adequate complex reconstructive case volume for independent practice. Study data were collected and managed using REDCap electronic data capture tools. Fellows that have not yet completed a clinical year were excluded. RESULTS: The ACGME data revealed a mean of 2.86 total BE cases per graduating fellow from 2010-2022, ranging from an average of 2.0 to 3.9 cases per fellow, with a median of 1.6. Performing only 5 BE cases during fellowship would place a fellow in the 90th percentile, yet some fellows completed >15 BE cases. We achieved an overall survey response rate of 79%, with 18/24 (75%) of PDs and 24/29 (82.8%) of current or recently graduated fellows completing the survey. For reference, 95.8% of fellows would feel comfortable performing a robotic pyeloplasty independently upon graduation, most commonly stating 16-20 cases are necessary for proficiency. Most fellows claim the same volumes are required for proficiency in BE cases, but only 13% (N=3) feel ready to perform these procedures independently and 21% (N=5) intend to do so in practice. PDs most commonly voted 11-15 BE cases are required for proficiency and 5 claim their fellows can perform BE cases independently upon graduation. 56.0% of fellows and 44.4% of PDs believe fellowship training can/should provide enough exposure to complex reconstructive cases to allow for proficiency. CONCLUSION: Case volumes of bladder exstrophy remain low, yet stable over the past 12 years with significant variation between fellows. The majority of fellows fall far short of the volumes they and their PDs feel would be necessary for competence and proficiency. Unsurprisingly, those few achieving an adequate experience level with BE cases in fellowship reported interest in managing it primarily in the future. Furthermore, there exists a disparity between trainees and PDs in whether a goal of fellowship is to sufficiently prepare fellows to perform these procedures by the time they graduate. To meet current and future global needs, institutions may need to supplement the current training model.