The centroid of the discrete components forming the overall radar return from a target onto which a homing weapon is being guided may not coincide with a desired aimpoint on the target. Herein proposed is the discrimination and comparison of returns from different portions of the weapon sensor's field-of-view, i.e. different portions of the target and guidance of the weapon in dependence upon the relative values of the differences between those returns. As a result, the weapon can hit say the centre of a tank turret roof rather than the probably heavily armoured area forward of the turret roof.