The availability of microcomputers, modeling langauges and general purpose spreadsheets has resulted in an increase in the use of models for decision making within organizatons. Decision makers with microcomputers on their desks and spreadsheet and modeling software can create models rapidly. Problems with model redundancy, consistency, integrity and security have prompted an increased interest in the design of model management systems (MMS). Several model management designs have been discussed in the literature. Different model representation techniques have been proposed. These include formal logic, semantic inheritance networks, frames, and relational representations. The approaches to model management are evaluated in respect to their model manipulation and model storage functions. A framework for the design of MMS is proposed based on the system design objectives and the system domain complexity. Advantages and disadvantages of each model representation method are identified. Application domains for the classifications are proposed which focus on the strengths and weaknesses of the model representation for supporting model storage and model manipulation functions. An example of the design of a MMS using the classification is presented.