Methods, devices and systems facilitate gastric retention of a variety of therapeutic devices. devices generally include a support portion for preventing the device from passing through the pyloric valve or esophagus wherein a retaining member may optionally be included on the distal end of the positioning member for further maintaining a position of the device in the stomach. Some embodiments are deliverable into the stomach through the esophagus, either by swallowing or through a delivery tube or catheter. Some embodiments are fully reversible. Some embodiments self-expand within the stomach, while others are inflated or otherwise expanded.