Here, we examine over two decades of empirical literature to explore the ways scholars have been working to reveal the changing set of policy and political conditions in which teachers unions are operating. In this context, we identify the conceptual models educational researchers have used to frame their research and the applications of these frameworks in the literature on teachers unions. Our findings reveal that the research on teachers unions over the past two decades provides deep historical context. Less evident in this research are explicit conceptual groundings to theory and how the theoretical/empirical literature is applied in inquiry.