Abstract: A system for rendering data recorded on recordable media unreadable, the recordable media having a unique identifier, the system comprising:—means for reading said unique identifier from a recordable medium (104);—means for comparing said read unique identifier with a stored record of one or more unique identifiers of recordable media required to be processed (109);—means for generating an output indicative of whether or not said read unique identifiers matches one of said one or more unique identifiers in said stored record; and—means for rendering data recorded on a recordable medium unreadable only if said read unique identifier matches one of said one or more unique identifiers in said stored record (110).