The Union List of Artist Names (ULAN) is a free online database of the Getty Research Institute using a controlled vocabulary, which by 2018 contained over 300,000 artists and over 720,000 names for them, as well as other information about artists. Names in ULAN may include given names, pseudonyms, variant spellings, names in multiple languages, and names that have changed over time (e.g., married names). Among these names, one is flagged as the preferred name. Although it is displayed as a list, ULAN is structured as a thesaurus, compliant with ISO and NISO standards for thesaurus construction; it contains hierarchical, equivalence, and associative relationships. The focus of each ULAN record is an artist. In the database, each artist record (also called a subject) is identified by a unique numeric ID. The artist's nationality is given, as are places and dates of birth and death (if known). Linked to each artist record are names, related artists, sources for the data, and notes. The temporal coverage of the ULAN ranges from Antiquity to the present and the scope is global. Artists may be either individuals (persons) or groups of individuals working together (corporate bodies). Artists in the ULAN generally represent creators involved in the conception or production of visual arts and architecture. Some performance artists are included (but typically not actors, dancers, or other performing artists). Repositories and some donors are included as well.