BACKGROUND Technical improvement in endoscopic and manometric technique has allowed direct manometry of the human sphincter of Oddi (SO). The aim of the present review is to describe the present status of physiologic and clinical knowledge of the SO, with emphasis on contributions from Danish Gastroenterology. RESULTS The SO is a zone with an elevated basal pressure with superimposed phasic contractions. It acts mainly as a resistor in the regulation of bile flow. Neurohormonal regulation influences the motility pattern. The contractions are under the control of slow waves. Clinical subgroups show abnormalcy in SO manometric pattern especially in patients with biliary or pancreatic pain without demonstrable organic substrate. Evidence suggests that endoscopic sphincterotomy may be of benefit in these patients.