A control system for an autonomous vehicle or robot comprises a plurality of high level controllers. Each high level controller is able to provide high level movement commands independently of the other high level controllers. A low level controller is arranged to receive the high level movement commands of one of the high level controllers and to convert said received high level movement commands into electrical outputs to a plurality of electrical motors/actuators for driving the vehicle/robot. A decision system, independent of the high level controllers, is configured to decide which one of the high level controllers is to be active. The active high level controller only is used provide the high level movement commands to the low level controller.