An incisionless fully endoscopic method of reducing the capacity of the stomach is provided to surgically treat obesity. The method is directed to endoluminal tissue approximation of a portion of the stomach, including at least a portion of the greater curvature thereof. The method includes a pattern of stitching in which a portion of the stomach is closed off. One stitching pattern causes the lateral portion of the stomach to be drawn to reduce the usable volume of the stomach while maintaining a pathway from the esophagus to the pylorus. As the stitching pattern advances, the fundus is automatically drawn downward so that it may be endoscopically approached for stitching in a facilitated manner. According to another aspect of the invention, another stitching pattern extends from the antrum to the fundus between the anterior and posterior portions of the stomach.