We argue that scholars of the presidency should begin to apply their rich descriptive understanding of White House organization and personnel to questions of causality. To help guide this effort, we offer a theory-driven empirical model that explains organizational performance. Importing theory from the public management literature, we show how scholars can use the Meier-O'Toole (MO) model to explain performance outcomes and dynamics for key political and policy functions within the institutional presidency. We introduce the MO model and discuss its potential impact on the field of presidency studies. F or longer than necessary, the scientific study of the presidency has labored under the reputation of being theoretically underdeveloped. Since at least 1977, when Hugh Heclo reported to the Ford Foundation on the dismal state of presidency research, scholars have been wringing their hands over this problem (Edwards and Wayne 1983; see also Edwards, Kessel, and Rockman 1993). Although some aspects of presidency studies have since seen considerable theoretical development, particularly research that examines linkages between presidents and external political arenas, the literature examining phenomena that occurs within the White House merits renewed attempts to develop empirical theory. 1 To answer this call for new theory-driven research on the internal politics of the executive branch, scholars need broad empirical theory that explains how the behavioral dynamics of actors within the White House shape presidential performance. 2 In this article, we introduce such a theoretical model: the Meier-O'Toole (MO) model. Imported from the field of public management, the MO model provides a rich theoretical explanation for why the modern presidency performs as it does. Our reference to the scientific literature on managing public organizations is appropriate because beneath the symbolic trappings and enormous amounts of power inherent in the modern presidency is a conventional public bureaucracy. 3 Moreover, the American presidency is a bureaucracy that itself is composed of a series of smaller bureaucracies, the success of which depends on how well these organizations, and the institution as a whole, are managed.This last point builds on the research of Walcott and Hult (1995Hult and Walcott 2004), who show that the functioning of the White House relies on the bureaucratization of specific important tasks. 4 Just as the president's administrative role centers on his ability to manage the numerous bureaucracies that compose the federal government, the skill with which the president does so depends on how well the internal bureaucracies of the White House are managed. Walcott and Hult provide scholars with an important base from which to develop empirical theory that explains presidential performance. Presidency scholars can extend Walcott and Hult's work by using the theoretical expectations derived from the MO model to examine how the functioning of these bureaucracies influences presidential performance.In this article...