Control of an autonomous vehicle

A method is provided for controlling a primary vehicle which can be driven in an autonomous mode and is also operable by a driver in a manual mode. The method comprises: determining failure of the driver to accept a request 32 to switch the primary vehicle to the manual mode when the vehicle is in the autonomous mode; determining a primary vehicle driving state 38; acquiring vehicle data from one or more surrounding secondary vehicles 40, 42; determining a contingency action 46 to take with the primary vehicle based on the primary vehicle driving state and the vehicle data from the or each secondary vehicle; and outputting the contingency action 48 to at least one system of the primary vehicle to drive the primary vehicle autonomously in accordance with the determined contingency action. A remote control also drives the primary vehicle autonomously, or may be used to communicate with secondary vehicles that are not close to the primary vehicle. Secondary vehicle data may be obtained through vehicle-to-vehicle communication.