The subject of this study was the development of a computer-based system for the modeling of costing assumptions in an academic department. Initially, costing assumptions were defined as those assumptions made in the selection of costing sources and apportioning procedures in cost studies. The major theme of this study was that the system should allow for multiple sets of costing assumptions to be modeled, and it should allow for a very low level of cost disaggregation. This modeling system allows costs to be attached to individual course enrollments, and it also allows multiple departmental cost studies to be performed simultaneously so that any two may be compared for sensitivity analysis.