The findings of a study performed to obtain an understanding of the frequency-dependent behavior of the automotive shock absorber are presented. Following a brief review of the literature on this topic and an identification of the various elements contained in the modern-day hydraulic shock absorber, the mathematical model developed to describe the pressure-flow phenomena occuring within an absorber is outlined. A brief accounting is given of the experimental techniques that were used to determine the pressure-flow characteristics of the valves, orifices, etc., typically found in present-day absorbers. The use of the analog computer to solve the resulting equations is briefly indicated, with primary attention being given to a comparison of simulation findings with experiment. The developed simulation is then used to explore and explain the mechanisms responsible for the hysteresis found to exist in the force-velocity relationship at frequencies in excess of 1 Hz.