The ARL Library Index as a Decision-Making Tool

In May of 1980 the Association of Research Libraries (ARL) adopted new criteria for membership in the association based, in large part, on what is known as the ARL Library Index. 1 This index is derived from a model containing ten categories, or variables, which characterize library size. While the Library Index model was developed as a measure of an institution's overall standing relative to the ARL membership, this author has found it to be useful, if properly employed, as a decision-making tool in short-term planning, programming, and budgeting in those operations affecting library size. This article describes the procedure for this application of the index.