General Motors has studied the Metro Guideway, an integrated multi-mode system of urban transportation that uses captive vehicles with automatic control on the guideway, and dual mode vehicles, capable of automatic control on the guideway and of manual control on ordinary streets and highways. The object of this paper is to define the communication interfaces in the Metro Guideway system, to configure an information flow system, and to formulate some considerations on the required channel capacity for the routing and scheduling tasks.