Abstract: A crash energy absorption system for a motor vehicle, formed of an assembly of panels of lightweight core material sandwiched within and bonded to reinforcing or stiffener skins. Preferably, the reinforcing or stiffener skins comprise fiberglass, graphite, Kevlar or Spectra reinforced polymers with any combination of fibers and/or fiber orientations, or metal sheets, or ceramic sheets, while the lightweight core material comprises a low-density, dimensionally stable material such as balsa wood, synthetic foam material such as polyurethane foam. The crash energy absorption system may take the form of removable parts that are replaceable after an accident, or may be formed as integral parts of a monocoque body, or as a part of a composite body load-bearing frame.