In this paper we present the development of a methodology for creating multilingual thesauri of period names based on CIDOC CRM, archeological theory and results from Computer Science and
Knowledge Representation. Periods are deÞ ned by identity criteria (coming from the archaeological evidence) rather than by time and place. A formal model in the form of XML DTD has been developed as a proposal of standardization for period thesauri. An example thesaurus of Helladic periods is used as a proof of concept
