Large pseudocysts may follow an episode of acute pancreatitis and are generally treated if symptomatic or enlarged after six weeks. In open surgery, a drainage procedure with the gastrointestinal tract is advocated. This video describes the technique for laparoscopic transgastric cystogastrostomy in a 42 year old patient biochemical investigations prior to detection by standard with a 20 cm pancreatic pseudocyst of the body of the pancreas. New techniques of endoluminal laparoscopic surgery may be applicable to the surgical management of large pseudocysts.