Self-locking removable apparatus and methods for manipulating and securing tissue are described herein. In creating tissue folds within the body of a patient, a tissue manipulation assembly may generally have tissue stabilizing members adapted to stabilize tissue therebetween, an engagement member slidably disposed through the stabilizing members and having a distal end adapted to engage tissue, and a delivery tube pivotable about the tissue stabilizing members. The tissue manipulation assembly optionally may be configured for removable attachment to an endoscope.