Knowledge is one of the organization's most important values that influencing its competitiveness. One way to capture organization's knowledge and make it available to all their members is through the use of knowledge management systems. A critical process in the whole knowledge management life cycle is validation. A Knowledge Base (KB) incorporated into such systems has to be verified or (more generally) validated. There have been many approaches to develop specialised procedures and techniques, aimed at assuring the highest level of knowledge quality, so the paper deals with practical guidelines of Knowledge Validation (KV). This paper defines certain principles useful in the validation procedures referring to the structural assumption for KV. Finally it presents our approach to build a corporate memory in industrial study case comparing with other case studies.