A control system for a vehicle subsystem (10) comprises a controller (12) arranged to control operation of the subsystem (10), a user input (16) connected to the system controller (12) and arranged to be operated by a user, and a sensor comprising a transmitter (22) associated with user input (16) and a receiver (26) associated with a first user, whereby the controller uses detection of a signal from the transmitter (22) by the receiver (26) to distinguish between operation of the user input (16) by said first user and operation of the user input by a second user.