Methods and devices are provided for performing various procedures using interchangeable end effectors. In general, the methods and devices allow a surgeon to remotely and selectively interchange various surgical end effectors within a patients body, thus allowing the surgeon to perform various procedures without the need to remove the device from the patients body. In one embodiment, a modular device is provided having an insertion device and a cartridge containing a plurality of end effectors coupled to or formed on the insertion device. The cartridge can be configured to move between various positions to allow an instrument shaft to be selectively mated to one of the various end effectors contained within the cartridge. For example, the cartridge can be moved to a desired position, and an instrument shaft can be advanced into a chamber in the cartridge to engage and remove an end effector from the cartridge, thus allowing the end effector to be used to perform a surgical procedure. Once complete, the instrument shaft can be retracted relative to the cartridge to return the end effector into its original chamber in the cartridge. The cartridge can then be repositioned to allow the shaft to engage and utilize another end effector.
