The authors present an approach to optimizing the design of a knowledge-based design (KBD) system so that it produces optimal or near-optimal results. It is subjective in nature, however, as a KBD system's performance is often justified by the examination of its designs by experts. One alternative, as shown here, is to apply the simulated annealing technique (SA) in designing a KBD system. During the design of a KBD system, two designs by a KBD system and a SA system are independently generated. The solution generated by the SA system is then used to critique a solution from the KBD system. To some extent, an objective measure is brought into the design of a KBD system. The authors investigate this SA-KBD approach in a telephone cable network design domain, and the results are encouraging.