Some scholars of American political development have used the phrase "partisan regimes" to refer to an important recurring pattern in American politics: a short, tumultuous period of partisan upheaval and political and policy change followed by extended stability This article develops the concept of a partisan regime as an ideal type that can help scholars not only explain variations among historical cases, but identify the different elements that contribute to the rise of regimes and understand what these potent coalitions do once they secure power The ideal type points to entrepreneurial leadership, political crises, and partisan narratives as the key contributors to the emergence of new governing orders. Furthermore, once a partisan regime achieves control, it only temporarily disrupts and remakes national policy politics, and political debate. After achieving its core priorities, the regime primarily operates to preserve its gains. The concept of a partisan regime therefore offers only a limited explanation for many policy changes that occur during the long periods between regime upheavals. Polity (2012) 44, 51-80. doi:10.1057/pol.2011.18; published online 14 November 2011