Most institutions of higher education have a mission that specifically addresses three areas: instruction, research, and service. The repertoire of activities and the complexity of the goals of the University Library mirror the goals of the institution, the academic units, and the faculty. The clients of the library are the students, the faculty, and the community at large in all three goal areas of the University; hence assessment of the library must take into account not only the three outcome areas, but the three client groups as well. More than a service unit for the institution's instructional activities, the library itself offers instruction in information retrieval and, as a research facility, interacts with the research strategies of all disciplines. Besides students and faculty, the library increasingly serves the wider community outside the institution, especially through electronic networks that extend nationally and internationally. The library's ability to access information through electronic networks also renders simple circulation figures or the number of holdings inaccurate as an evaluation measure. The methodology used to assess the library must take these realities into account. The best evaluations will be comprehensive, taking care to sample all client groups. A variety of techniques should be used, including print questionnaires specifically designed for the library being evaluated; individual interviews that take into account the complexity of library services and can elicit satisfactory information; focus groups; observation of library use; document analysis, and transactional analysis. A comprehensive assessment would call for a combination of all these methods, if comprehensive is defined as addressing the service of all client groups in all service areas. A more reasonable approach would be to design focus questions that state the most important concerns of the library and build methodological packages that address those concerns in a frugal manner. (Contains 19 references.) (KRN)