Abstract: A financial transaction customer carries a card key containing a unique, machine-readable code. The code is an encrypted data set representing the user's thumbprint. A scanning system senses the user's thumbprint on or adjacent the card key as he turns the card key in a keyhole. The code and thumbprint are read by laser and must match previously recorded data before an indication of satisfactory identification can be returned. The identification system further includes a centralized database containing data and processing software for recognizing the encoded card keys of the system, in addition to data and processing software for authenticating a user's thumbprint. A network links this centralized database to a number of remote terminals at sites where identification is required. Such a distributed network is common in today's identification systems involving more than one remote site.