A method for verifying knowledge bases that is based on the unification of rules is discussed. One characteristic that distinguishes this approach from other verification tools is that it infers some of the rules that are not explicitly given in the rule base and considers their effect on the verification process. The method can determine conflicting, redundant, subsumed, circular, and dead-end rules, redundant if conditions in rules, and cycles and contradictions within rules. The method has been implemented in a computer program called UVT (for unification-based verification tool) and tested on sample knowledge bases.< >