This paper explores the history of descriptor lists (DLs)—scientific standards for documenting plant genetic resources—which have been published by Bioversity International since 1976 (formerly IBPGR 1974–1991; IPGRI 1991–2006). Each DL represents an important tool; together, they constitute the basis for a standardized characterization system that provides an internationally agreed format and universally understood ‘language’ for plant genetic resources data. The paper also presents an analysis of data collected through questionnaires and web statistics on the impact of DLs in order to understand their use by major stakeholders. The usefulness of Bioversity’s DLs was measured in terms of their value in facilitating the establishment of databases, and improving collaborations and information exchange among organizations. Most survey respondents reported that they not only used Bioversity’s DLs, but recognized them as the standards for plant genetic resources data collection and management. Bioversity’s DLs are widely respected because they are developed by large groups of crop specialists. Together, the DLs are helping Bioversity to meet the ambitious objective of establishing a Clearing-House Mechanism as set forth by the Convention on Biological Diversity (CBD) Article 18.3, which seeks to promote and facilitate information exchange among parties, Governments and stakeholders in order to assure a full implementation of the CBD. A number of areas for improvement were identified, although some of them are either outside Bioversity’s mandate or depend on human or financial capital for implementation.