Abstract: A method of controlling a computer (12) system (10) comprising the steps of: disposing a computer (12) in an operating space and placing the computer (12) in a lockout mode to prevent operation of the computer (12) software by a user. A database (26) of authorized user codes is compiled in the computer. A transponder (20) places a first authorized user code in the operating space and a transceiver (18) scans the operating space for the presence of a transponder transmitting an authorized user code and senses the presence of the first authorized user code in the operating space. A comparator (29) compares the first authorized user code to the database (26) for verification to unlock the computer (12) for use by the first authorized user in response to sensing the authorized user code in the operating space. The authorized user then is free to operate the computer software while the sensing for the presence of a transponder (20) transmitting an authorized user code in the operating space is continued.