This contract is designed to support research and analysis in the area of nomenclature used for protein sequence database description. It will focus on a mapping of keywords in the PIR vocabulary to words in the MeSH vocabulary, and a mapping of taxonomic terms in both vocabularies. The objective of this mapping effort is to relate all synonymous terms in both vocabularies and to identify underlying common concepts. The result of these analyses will be examined in the light of possible modification of the PIR nomenclature system with the overall goal of bringing various taxonomic and keyword systems into closer accord.