Abstract: The system comprises a spring between the vehicle body and each wheel, a shock absorber associated with each spring and which is switchable electromagnetically between soft and hard settings, one or more accelerometers measuring vertical acceleration of the vehicle body, an electronic filter for filtering the signals from the accelerometer to select a band width of frequencies, either side of the primary ride frequency of the vehicle, and control means for switching the shock absorbers between the soft and hard settings whenever a pre-determined level of vertical motion within this band width is exceeded either in the bump or rebound directions.