This article, which presents an interdisciplinary research agenda grounded in a constructivist institutional approach, begins by unpacking relevant terms. It explains the new institutional approach in political science that simultaneously narrows the focus and broadens the scope of political research by encouraging a return to the "political" in political science while also opening political research to a variety of other disciplinary approaches. It then explores the ontological and epistemological assumptions underlying a constructivist approach. Such assumptions are an integral if often unacknowledged part of any research effort, interdisciplinary or not. The main part of the article then offers an interdisciplinary research agenda describing how political science, sociology, and history can provide an integrated constructivist guide to the study of political institutions. The article suggests employing a feld of consciousness approach to integrate the work of these three disciplines in order to situate interdisciplinary research on political institutions on the common ground of institutional standard operating procedures.