The multilingual European Thesaurus on International Relations and Area Studies (European Thesaurus) is a special subject thesaurus for the field of international affairs. It is intended for use in libraries and documentation centres of academic institutions and international organizations. The European Thesaurus was established in a collaborative project involving a number of leading European research institutes on international politics. It integrates the controlled terminologies of several existing thesauri. The European Thesaurus comprises about 8,200 terms and proper names from the 24 subject areas covered by the thesaurus. Because of its multilinguality, the European Thesaurus can not only be used for indexing, retrieval and terminological reference, but serves also as a translation tool for the languages represented. The establishment of cross-concordances to related thesauri extends the range of application of the European Thesaurus even further. They enable the treatment of semantic heterogeneity within subject gateways. The European Thesaurus is available both in a seven-lingual print-version as well as in an eight-lingual online-version. To reflect the changes in terminology the European Thesau-rus is regularly being amended and modified. Further languages are going to be included.