The objective of this paper is two-fold: to propose a theoretical framework and model for studying organizational innovation in research libraries and to set forth propositions that can provide directions for future empirical studies of innovation in research libraries. Research libraries can be considered members of a class of organizations referred to here as institutional nonprofits. As such, these organizations inherit many of the innovative properties that are associated with the broader sector of service organizations. However, institutional nonprofits have unique characteristics that distinguish them from other service organizations such as government agencies and for-profit service firms. In this paper, institutional theory is used to explain the forces that are acting on the research library. Research from organizational learning, structural contingency theory, and typologies of service organizations are used to establish a more encompassing innovation framework. Based on the literature review, the theoretical framework, and empirical studies, this paper presents a process model and propositions that characterize how the research library might innovate. These propositions can be tested in empirical studies to develop a fuller understanding of innovation in research libraries.