An apparatus controls a vehicle having an engine including a throttle having a throttle position sensor, the throttle being adjustable to vary the speed of the vehicle, a transmission having an input shaft, an output shaft, and drive means there between providing a variable drive ratio, and a transmission controller for controlling the drive ratio between said input and output shafts, and at least one axle in driving connection with the output shaft of the said transmission, wherein the controller comprises a selector operable to select between first and second modes of operation, in said first mode the throttle and transmission are operated individually by the operator in said second mode, operation of the throttle and transmission is interconnected and performed by means of a computer program.