This paper shall review Metso Minerals' current 3D Discrete Element Method (DEM) modeling techniques, developed to allow a detailed study of the interactions of crushing design variables with actual rock mechanics. A standard DEM approach cannot be applied to systems where size reduction is an important element in the flow of particles, such as industrial crushers. In these systems, it is necessary to physically decrease the particle sizes in a realistic way, as they are transported through the device. Metso Minerals has therefore developed a breakage model that incorporates elements of Population Balance Modeling (PBM) techniques to describe breakage as a function of the loads on the individual rocks. The combination of this breakage model with DEM has therefore allowed the development of a multi physics based comminution model that can be applied to crusher development. This model is sensitive to all aspects of crusher design including crusher machine parameters and the ore characteristics. This physics based virtual comminution model will enable engineers to optimize the design development of future crushers by allowing a wider range of values for the crusher variables to be investigated in a rapid, yet more detailed manner, without the need for the traditional expensive and lengthy prototype testing. (C) 2009 Elsevier Ltd. All rights reserved.