:),Thanks for the previous answer, for your information, i'm a student working on a KM project with just a brief idea.Basically, we would want to have a knowledge repository to store documents, procedures etc. for future reference. Then, there should be a retrieval engine right?The project team has decided to use ontology to represent the knowledge structure. So, i would to know more about developing a retrieval engine that use ontology as a knowledge structure, on what it will needs, how will it be and related concepts in order to implement it using openACS. :) .Looking forward for any assistant.