The BCH Thesaurus provides a pre-defined list of terms, related synonyms and translations used in the specific context of records registered with the Biosafety Clearing-House. It establishes the relationships between these terms to facilitate retrieval of records. The BCH Controlled Vocabulary uses the ‘preferred’ terms from the BCH Thesaurus to classify records in the BCH, which allows users to consistently register and search for information in the databases in multiple languages.