The Decision Support Problem (DSP) construct is anchored in the notion that design is fundamentally a decision making process. Key is the concept of two types of decisions (namely, selection and compromise) and that any complex design can be represented through modelling a network of compromise and selection decisions. In a computational environment the DSPs are modeled as decision templates. In this paper, modular, executable, reusable decision templates are proposed as a means to effect design and to archive design-related knowledge on a computer. In the context of the compromise Decision Support Problem (cDSP) we address two questions:
1. What are the salient features for facilitating the reuse of design decision templates?
2. What are the salient features that facilitate maintaining model consistency when reusing design decision templates?
Here, the first question is answered by the identification of reuse patterns in which specific modifications of the existing cDSP templates are made to adapt to new design requirements, and the second question is answered by developing an ontology-based cDSP template representation method in which a rule-based reasoning mechanism is used for consistency checking. Effectiveness of the ontology-based cDSP representation and reuse is demonstrated for the redesign of a pressure vessel.