Abstract: A hybrid actuation system comprises first and second actuator arrangements (10, 12) arranged to apply first and second output loads respectively to a common element (14). A control method for controlling the operation of the hybrid actuation system includes the steps of supplying first and second demand signals to the first and second actuator arrangements (10, 12) respectively to cause movement of the common element (14) into a demanded position, monitoring the first and second output loads applied by the first and second actuator arrangements (10, 12) and generating an output signal indicative of the difference between the first and second output loads. The first and second demand signals are corrected in response to the output signal to compensate for any difference between the first and second output loads, thereby to ensure the first and second output loads applied to the common element (14) are substantially identical and synchonised.