Management Information Systems (MIS) provide management with information necessary for decision making in all areas of the firm. This paper presents a conceptual approach to construction of MIS simulation models. Such models may be used for efficient structuring of real world systems. The approach used herein incorporates a simple system of flow diagramming the functional elements of the MIS. From the flow diagrams a set of difference equations is developed to provide a model structure for computer simulation runs. The "quality" of the MIS is determined by the information content of the data provided for the management decision making.