of the other KOSs. Where mapping is not a sensible option, the standard recommends other forms of complementary vocabulary use. Similarly on the Internet there is an opportunity to make a simultaneous search of repositories and databases that have been indexed with different KOSs, on an even wider scale. Interoperability between the different networks, platforms, software applications, and languages (both natural and artificial) is reliant on the adoption of numerous protocols and standards. ISO 25964-2 is the one to address interoperability between structured vocabularies, especially where a thesaurus is involved. Related standards Since Part 1 of ISO 25964 was published it has been adopted by the national standards bodies in a number of countries. For example, The British Standards Institution (BSI) in the UK has adopted it and labelled it unchanged as BS ISO 25964-1. At the time of writing similar consideration is under way for Part 2. The American standard ANSI/NISO Z39.19 - Guidelines for the Construction, Format, and Management of Monolingual Controlled Vocabularies covers some of the same ground as ISO 25964-1. It deals with monolingual lists, synonym rings and taxonomies as well as thesauri, but does not provide a data model, nor address multilingual vocabularies or other aspects of interoperability, such as mapping between KOSs. Where the two standards overlap, they are broadly compatible with each other. NISO is actively involved in both standards, having participated in the work of developing ISO 25964 as well as running its secretariat. The W3C Recommendation SKOS (Simple Knowledge Organization System) has a close relationship with ISO 25964 in the context of the Semantic Web. SKOS applies to all sorts of “simple KOSs” that can be found on the Web, including thesauri and others. Whereas ISO 25964-1 advises on the selection and fitting together of concepts, terms and relationships to make a good thesaurus, SKOS addresses the next step - porting the thesaurus to the Web. And whereas ISO 25964-2 recommends the sort of mappings that can be established between one KOS and another, SKOS presents a way of expressing the mappings when published to the Web. See also SKOS ISO 2788 ISO 5964 Thesaurus (information retrieval) References External links ISO 25964-1 Discussion of BS 8723 data model the ISO TC46/SC9/WG8 page an XML-schema for exchange of ISO 25964 thesauri the ISO 25964 based ontology, a SKOS and SKOS-XL extension Library science Thesauri 25964-1