The authors develop a framework for addressing the question of truth in librarianship and in doing so attempt to move considerations of truth closer to the core of philosophical debates within the profession. After establishing ways in which philosophy contributes to social scientific inquiry in library science, the authors examine concepts of truth currently found in the literature. Analysis reveals that only scattered attention has been given to this issue. As a result, there is a lack of clarity about the relationship between theories of truth and the practice of librarianship. The authors review the three prevailing theories of truth in philosophy and then introduce a new construct of truth rooted in an early version of historicism. The authors conclude that this theoretical framework offers a new method for understanding how the objective practices of librarianship only can be adequately explained by considering their place within a contextualized process of historical development.