Finite element analysis was used in the numerical assessment of the compressive impact response of a range of two- and three-dimensional truncated pyramidal polystyrene foam shapes, of the type used in protective packaging. The results were validated through the experimental impact testing of physical components. For both the truncated 2-D and 3-D pyramids, the predicted initial yield forces were within 25% of the experimental data, and the force at 50% strain within 10%, for a range of taper angles, so long as the uniaxial compressive hardening data ignored the initial stress plateau. The shape of the force-displacement response was related to the geometry of the pyramids. The observed deformation fields, on the sides of 3-D pyramids, confirmed features of the FEA predictions. (C) 2002 Elsevier Science Ltd. All rights reserved.