The Unified Medical Language System has been a major project of the National Library of Medicine for the past 12 years. There is a considerable amount of information (and some misinformation) about it published. The web site is worthwhile as a source of information about the project, including a bibliography, fact sheets, and a license agreement for persons interested in using the products of the UMLS. In lieu of citing articles within this text, let me point you to that bibliography. Particularly significant are the following papers:

1. McCray AT, Nelson SJ. The representation of meaning in the UMLS. Methods Inf Med 1995 Mar;34(1-2):193-201.

2. Lindberg DA, Humphreys BL, McCray AT. The Unified Medical Language System. Methods Inf Med 1993 Aug;32(4):281-91.

3. Cimino JJ. Formal descriptions and adaptive mechanisms for changes in controlled medical vocabularies. Methods Inf Med 1996 Sep;35(3):202-10.

4. Tuttle MS, Nelson SJ. The role of the UMLS in 'storing' and 'sharing' across systems. Int J Biomed Comput 1994 Jan;34(1-4):207-37.

There are experiences and observations from that project relevant to taxonomy authority issues. A Biblical analogy is worthwhile here: It appears that much of the taxonomy issues relate to where Adam was told to name the creatures; much of what the UMLS is approaching is a somewhat later problem, that depicted in the story of the Tower of Babel. Nevertheless, a close examination of the issues faced and methodology used in the UMLS may help guide taxonomists away from some of the pitfalls.