A system for controlling an operative parameter of a harvesting header (18) of an agricultural harvesting machine (10) comprises a first sensing arrangement for sensing a property of a field in front of the header (18) in a contact-less manner, a second sensing arrangement for providing a signal suited to derive a value of an adjustable work parameter of the header (18), an actuator (58, 68, 98, 102, 70) for adjusting the work parameter, and a control unit (46) for determining a control signal for the actuator (58, 68, 98, 102, 70) based on the signal from the first sensing arrangement and on the signal from the second sensing arrangement. The second sensing arrangement is arranged to detect the position of a reference point, which indicates the work parameter, in a contact-less manner, and that the first sensing arrangement and the second sensing arrangement are relatively fixed.
