A 42-year-old man presented with acute right upper quadrant abdominal pain 2 years after open cholecystectomy. Evaluation revealed cholecystitis in a second gallbladder and a second cholecystectomy was performed. Acute right upper quadrant abdominal pain after cholecystectomy presents a wide differential diagnosis, including the often idiopathic and difficult to manage postcholecystectomy syndrome. Emergency physicians should be aware of the most common causes of pain in these patients. Previously unrecognized congenital abnormalities of the biliary system should be considered when the diagnosis is not clear, as highlighted by this case report.[Shapiro T, Rennie W: Duplicate gallbladder cholecystitis after open cholecystectomy. Ann Emerg Med May 1999;33:584-587.]