Simulation experts know very well that there are similarities between the models they build for different manufacturing systems. This article describes a module based generic model generator for discrete manufacturing systems. The module based generator was developed from a group technology (GT) classification scheme. The GT scheme uses common model features as a basis for creating generic model components. Specific user models are constructed by modifying and configuring the generic models rather than building them from scratch, thus reducing the effort and skill expected of the user in the process of model abstraction, construction, and validation/verification.