An endoscopic fastening system having a diameter sufficiently small so that the fastening system is slidably insertable into a working channel of a flexible or rigid endoscope for performing a stapling, clipping, or other fastening operation, comprises one or more fasteners, and a fastener delivery and deployment assembly. One or more fasteners being disposed in a substantially closed prefiring configuration inside the fastener delivery and deployment system are configured for being delivered and deployed into a target tissue while remaining in a substantially closed configuration throughout the entire operation. Other related embodiments of fasteners and their respective delivery and deployment assemblies enabling fastening operations in conjunction with a flexible or rigid endoscope are described.