As health care delivery becomes increasingly focused on patient-centered models, interventions such as patient navigation that have the potential to improve care coordination garner interest from health care managers and clinicians. The ability to understand how and to what extent patient navigation is successful in addressing coordination issues, however, is hampered by multiple definitions, vague boundaries, and different contextual implementations of patient navigation. Using a systematic review strategy and classification method, we review both the conceptual and empirical literature regarding navigation in multiple clinical contexts. We then describe and conceptualize variation in how patient navigation has been defined, implemented, and theorized to affect outcomes. This review suggests that patient navigation varies along multiple dimensions and that the variation is related to differing resources, constraints, and goals. We propose a conceptual model to frame further research and suggest that research in this area must carefully account for this variation in order to accurately assess the benefits of patient navigation and provide actionable knowledge for managers.