Metrics have been routinely employed in the development of traditional software. With the adoption of the Capability Maturity ModelSM from SEI, the formal incorporation of metrics into the development process is mandated for higher levels of development practice. In the case of knowledge-based systems (KBS), very little use of formal metrics is reported. This paper examines some of the reasons for this situation, and provides a suite of metrics that can be employed in the development of KBS.