A gastroenterologic sleeve is anchored within the digestive tract, without tissue-puncturing mechanisms, by providing anchoring mechanisms that utilize the inherent shape of the stomach to prevent sleeve migration. In at least two embodiments, the anchoring mechanism expands to conform to the interior stomach walls. In other embodiments, internal pessary rings are held in place at the gastroesophageal junction by an external band. A delivery device is provided for implanting the various device transesophageally.
