Thirteen women aged 21 to 47 years were encountered with intermittent attacks of typical biliary type pain associated with vomiting and tenderness in the right upper abdomen, but the gallbladder filled normally during cholecystography and no stones were identified. Jaundice was not a feature and both liver function tests and serum amylase levels were normal. The pain was reproduced in each of the patients under carefully controlled conditions by the administration of cholecystokinin. In 12 who underwent cholecystectomy, no gross abnormality was found in the biliary tract or pancreas and no consistent pathological abnormality was detected in either the gallbladder or cystic duct to explain the pain. The patients, followed for 3 to 44 months, were relieved of their pain after operation. Although biliary pain is usually due to gallstones, the pain in these patients appeared to arise from the gallbladder and/or cystic duct in the absence of apparent obstruction. Nine of them also had a functional disturbance of the gastrointestinal tract. Six of these had emotional problems and the biliary tract disorder appeared to be part of a generalized disturbance in gastrointestinal function associated with emotional tension. However, in 4 patients, the gastrointestinal disorder was limited to vomiting which occurred only in association with pain and no emotional disorder was present. The etiology of the biliary pain in these patients is unknown.