A method for treating obesity by reducing the volume and/or alter the functioning of the gastric cavity to limit food consumption and induce early satiety. The method includes accessing the cavity endoscopically to visualize the interior of the cavity. The peritoneal cavity is accessed through a small incision in the abdominal wall. Using endoscopic visualization, suture anchoring devices are introduced into the peritoneal cavity through the incision and deployed from the exterior surface through the gastric cavity wall. Suture from pairs of the anchoring devices is drawn through the gastric cavity wall and tightened outside of the cavity to form a serosa to serosa plication. Any number of plications may be formed in the cavity wall and the contacting tissue within a plication may be treated to promote healing and a more durable bond.