A system for stabilising a vehicle combination comprising a towing vehicle and a towed vehicle (2, 3), said system including: a trailer brake system on the towed vehicle (2, 3) which may be operated together with the vehicle brake system on the towing vehicle as well as independent from said vehicle brake system; means for detecting at least one signal corresponding to at least one driving condition, the driving condition detection includes detecting at least one of the following driving conditions: (a) ambient temperature; (b) road inclination; (c) steering wheel angle; (d) vehicle combination weight; (e) auxiliary braking of the towing vehicle with a braking torque above a predefined limit; (f) vehicle combination speed; (g) the braking balance between the towing vehicle and the towed vehicle; means for computing said at least one detected signal and comparing said at least one detected signal with a corresponding predetermined value representing a potentially critical driving condition; characterized by a switch operable to allow independent operation of the trailer brake system in response to a detected potentially critical driving condition; and a trailer braking actuation arrangement operable to automatically operating the trailer brake system in response to the activation means by applying temporary ESP interventions consisting of short repeated trailer brake actuations of repetitive brake impulses of a brake force level (F t) strong enough to significantly affect the vehicle combination but not strong enough to cause significant trailer brake wear, fading or glazing problems, wherein a brake force level (F b) for reducing speed of the vehicle (1, 2, 3) is higher than the proactive stabilising trailer brake actions on the towed vehicle (2, 3) so as to achieve a proactive stabilization of the vehicle combination. a trailer brake system on the towed vehicle (2, 3) which may be operated together with the vehicle brake system on the towing vehicle as well as independent from said vehicle brake system; means for detecting at least one signal corresponding to at least one driving condition, the driving condition detection includes detecting at least one of the following driving conditions: (a) ambient temperature; (b) road inclination; (c) steering wheel angle; (d) vehicle combination weight; (e) auxiliary braking of the towing vehicle with a braking torque above a predefined limit; (f) vehicle combination speed; (g) the braking balance between the towing vehicle and the towed vehicle; (a) ambient temperature; (b) road inclination; (c) steering wheel angle; (d) vehicle combination weight; (e) auxiliary braking of the towing vehicle with a braking torque above a predefined limit; (f) vehicle combination speed; (g) the braking balance between the towing vehicle and the towed vehicle; means for computing said at least one detected signal and comparing said at least one detected signal with a corresponding predetermined value representing a potentially critical driving condition; characterized by a switch operable to allow independent operation of the trailer brake system in response to a detected potentially critical driving condition; and a trailer braking actuation arrangement operable to automatically operating the trailer brake system in response to the activation means by applying temporary ESP interventions consisting of short repeated trailer brake actuations of repetitive brake impulses of a brake force level (F t) strong enough to significantly affect the vehicle combination but not strong enough to cause significant trailer brake wear, fading or glazing problems, wherein a brake force level (F b) for reducing speed of the vehicle (1, 2, 3) is higher than the proactive stabilising trailer brake actions on the towed vehicle (2, 3) so as to achieve a proactive stabilization of the vehicle combination.