This study focuses on patients who have been diagnosed with pancreas divisum and have had at least 2 episodes of pancreatitis. The purpose of the study is to determine whether endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy reduces the risk of pancreatitis or the number of recurrent pancreatitis episodes in patients with pancreas divisum. ERCP with sphincterotomy is a medical procedure that is often performed in patients with unexplained, recurrent acute pancreatitis who also have pancreas divisum. For the procedure, doctors use a combination of x-rays and an endoscope (a long flexible lighted tube) to find the opening of the duct where fluid drains out of the pancreas. A cut is made in the opening of the duct to allow better drainage of fluid from the pancreas. The goal of the procedure is to reduce the risk of future attacks of pancreatitis. Participants will be randomly assigned to have an endoscopic ultrasound plus an ERCP with sphincterotomy, or an endoscopic ultrasound plus a "sham" procedure (meaning participants will be treated as if they are having the ERCP with sphincterotomy, but the procedure will not really be performed).