Endoscopic retrograde sphincterotomy was performed on four sedated pigs, ages 3-4 months, using a standard human duodenoscope and papillotome. Sphincterotomies, 1 cm in length, were well-tolerated, and all animals recovered promptly, spontaneously regained gastrointestinal function, and gained weight. The first three animals were sacrificed after one week, and autopsy revealed no complications. The fourth animal was sacrificed immediately following the procedure, and no evidence of perforation was found. These observations demonstrate that the pig is a valid experimental model for endoscopic sphincterotomy. Its use in training is limited by technical and anatomic differences from humans. Potential uses of this technique in research are discussed.