The intravenous administration of sincalide, the C-terminal octapeptide fragment of cholecystokinin, affords safe and effective means for gallbladder contraction with resultant cystic and common bile duct visualization. Intravenous sincalide circumvents the problem of unpredictability of response of the gallbladder to a fatty meal and variability in the rate of release of endogenous cholecystokinin. Peak gallbladder contraction occurs earlier than with a fatty meal.