Background: While the role of EUS in the evaluation of pancreaticobiliary (PB) disorders in adults is well established, its utility in children remains unproven. This prospective study evaluates the feasibility, the safety, and the impact of EUS in the evaluation of PB disorders in children. Methods: All children (<18 years) referred for ERCP for evaluation of suspected PB disorders who underwent EUS before scheduled ERCP. The main outcome measure was to evaluate the impact of EUS in the evaluation of PB disorders in children. EUS was considered to have a significant impact if a new diagnosis was established or if the findings altered subsequent management. Results: Fourteen patients (mean age 13 years; range 5-17 years) underwent 15 EUS procedures over a 3-year period. Main indications were the following: acute or recurrent pancreatitis (6 patients), suspected biliary obstruction (5), and abdominal pain suggestive of PB origin (3). EUS diagnosed chronic pancreatitis (3 patients), idiopathic fibrosing pancreatitis (2), carcinoid tumor (1), pancreatic pseudocyst (1), pancreas divisum (1), choledocholithiasis (1), duodenal duplication cyst (1), and normal (4). Diagnosis of idiopathic fibrosing pancreatitis and carcinoid tumor was established by EUS-guided FNA. The procedure was successful in all patients, and no complications were encountered. EUS had an impact on patient management in 93% of cases: established new diagnosis (10), precluded need for ERCP (9), and provided additional information that facilitated focused endotherapy (4). A limitation was the small number of enrolled patients and absence of long-term clinical follow-up. Conclusions: EUS and EUS-guided FNA are feasible, safe, and have significant impact that alters subsequent management in the majority of children with PB disorders. Further studies and dissemination of information is required to facilitate its increased application in children. Copyright © 2005 by the American Society for Gastrointestinal Endoscopy.