The Dublin Core Metadata Initiative (DCMI) maintains a vocabulary of several dozen metadata terms, most notably the fifteen-element Dublin Core. Within DCMI, however, discussion has focused more on the practices, policies, and models around the Core. Its initial single-resource data model is evolving towards a fuller framework for evaluating the diversity of Dublin Core implementations. Terms (and their historical versions) are identified with URIs, documented onWeb pages and in formal schemas, indexed in registries, and cited in application profiles. With low-overhead maintenance processes, DCMI seeks to balance the growth of a central standard against recognition and re-use of other, complementary vocabularies.