Although academic libraries have a long tradition of program assessment, in the past the results have been more meaningful internally than externally. Recent changes in the conceptualization of libraries' role in higher education and advances in measurement tools will likely provide answers to different questions, particularly the relationship of library services and resources to student learning and success. This paper discusses the following: (1) The tradition of assessment in libraries; (2) The current state of affairs and challenges of assessing the following library components--instruction, services, and resources; and (3) Implications for the future of library assessment. Much work has yet to be done in the assessment of libraries. Hopefully these future endeavors will illuminate relationships between elements of the library and student learning and success. Such information could only help the efficacy of libraries around the country.