This study presents a methodology for describing, analyzing, and evaluating the public service functions of serial file syste111:?, with emphasis on evaluation. The system in a university departmental n many library settings, a serials known-item search requires a patron to consult a complex network of bibliographic and holdings records reflecting a unique compilation of cataloging codes, holdings statement standards, and in-house technical services policies and practices. This record network is organized into a cluster of separate and often single-purpose files that include information on current issue receipts, bound volume holdings, and claims, bindery, and other processing activities. The patron can access some files directly, while others are consulted by library staff on behalf of the patron. In most libraries, this serial file system includes the union catalog, shelflist, serials checkin files, a variety of in-process records and, in many cases, a separate list of serials holdings.The investigators who undertook the project described in this paper were interested in exploring the overall question of how the public service functions of such systems can be defined, described, and evaluated. This process begins with a library delineating what patron-oriented functions it has assigned its serial file system, specifically or by default, and then proceeds to a description of the system and, finally, to an evaluation of how well the system fulfills its public service responsibilities. The current study focuses most specifically on the evaluative facet of this process. The intent is to suggest a useful approach toward the evaluation of current systems, either to improve their effiElizabeth Hanson is associate librarian, Indiana University Libraries, and Judith Serebnick is associate professor,