Countless organizations have their own intricate and well-developed thesauri that have been refined over many years. With consummate converters, these thesauri can become a strong and useful element on the semantic web. Like the Thésaurus from the National Cancer Institute, many are available in an unusual form of XML, or not in XML at all. As in this case, simple translations using standard XML parsers often will not be a reasonable solution for making the transition to RDF or OWL. The most time.