Abstract: The present invention provides a system and method for authorizing a user of a tractor-trailer to drive the tractor-trailer out of a plurality of tractors and trailers. The system comprises modules such as tractor modules and trailer modules. Each module comprises a user interface and a transceiver. A tractor module is located in each of the tractors and is uniquely associated with that tractor. The tractor module is also operatively associated with systems of that tractor. A trailer module is located in each of the trailers and is uniquely associated with that trailer. The trailer module is also operatively associated with systems of the trailer. In the system, a unique code is associated with each user and a central station sends this unique code to the modules, so that the modules enable the user to drive the tractor with the trailer.