Doing Research at the Library of Congress

IIA. Three Basic Principles of Library of Congress Subject Headings

a. Uniform heading

The first principle in the construction of the LCSH list is that of uniform heading, which addresses the problem of synonyms, variant phrases, and different language terms for the same concept. Librarians who create a catalog using this system choose, wherever possible, one term for the subject at hand from the many possible keywords, and then group all relevant material under that one category term (Cuba--History--Invasion, 1961 in the above example) rather than filing the same works under each of several different terms scattered throughout the alphabet. Since the full list of relevant books appears under only one of the many possible terms referring to it, the catalogers insert cross-references in the alphabet at the positions of several of the other possible words, in order to steer researchers to the one main grouping.