Abstract
Design optimization problems and VLSI microprocessor design in particular, are complex problems with some characteristics that make them very different from the problems that AI researchers have traditionally studied. Case based reasoning is a valuable tool that can be used to make these problems tractable. Traditional case based methods with their use of REPLAY based techniques are unsuitable because they rely on the use of design records and decision trees. CONSTRAINEDREDO is a new technique that does not use design records but instead relies on an analysis of the solution and the propagation of information through constraints. These constraints are not on the design decisions but only refer to the mapping between the problem specification and the solution. The technique has been tested in a real-world domain, that of VLSI microprocessor design.