A paper shredder is configured like a conventional paper shredder except that the shredding mechanism is located in a removable cartridge. This allows a single paper shredder housing to be rapidly converted from one shredding pattern to another by simply changing the shredding cartridge. Furthermore, shredding cartridges can be readily replaced whenever the shredding mechanism jams or fails in some other manner. This simplifies repair and servicing of the paper shredder.