Abdominal ultrasonography of a 9-year-old girl with nonspecific gastrointestinal complaints demonstrated findings suggestive of a choledochal cyst. Hepatobiliary scintigraphy, performed to assess the physiologic status of her biliary system, demonstrated intraductal stasis and poor drainage from the biliary tree into the bowel. The combination of these two noninvasive studies provided a highly accurate preoperative assessment of this patient's condition and correlated well with the operative findings.