This study develops a leader-centric theory of civil-military relations that expands upon three broad areas of research. Specifically, the study suggests that leaders will evaluate multiple threats to their political survival and will ultimately implement strategy that is most likely to keep them in power. While Downs (1957) has noted such a tendency in democracies, this study expands this rationale to authoritarian regimes by focusing on the primary means of authoritarian removal: the military coup. In contrast to the state-centric nature of traditional international relations theory, this dissertation finds that leaders frequently undermine the power of the state in order to accomplish the self-interested goal of political survival. First, the study carefully describes a number of coup-proofing strategies that leaders can implement. These are broadly defined in terms of influencing either the military’s willingness or its ability to attempt a coup. In addition to testing the effectiveness of these strategies, this study also theoretically explores the implications of coup-proofing for other political development of the state: interstate and intrastate conflict. Second, the study considers the influence of coup-proofing on interstate conflict. This study builds on the diversionary literature by investing coup risk as an incentive to use diversionary tactics as well as coup-proofing as a potential disincentive. The latter can both undermine the necessity of diversion as well as military capabilities, making leaders less capable of utilizing international conflict as a political tool. Third, the dissertation considers the influence of coup-proofing on intrastate conflict. The theory argues that the capability-reducing practice of coup-proofing can have important domestic consequences. Specifically, the practice can increase the mobilizational potential of would-be insurgents, can reduce the mobilizational capacity of the state, and leaders that are particularly fearful of a coup will likely tolerate the rise of an insurgency.