Civil-military relations scholarship forecasts that governments fearing coups d’état and facing belligerent external and internal adversaries face a dilemma. Governments can coup-proof to reduce coup risk, but such measures reduce military effectiveness. Conversely, if they eschew coup-proofing to maintain military effectiveness, they risk coups. This paper explains how governments facing coup threats and belligerent adversaries can alleviate this dilemma. It first describes five coup-proofing measures that generally reduce military effectiveness, such as politicized promotion and reduced training, and two other coup-proofing measures that do not reduce effectiveness, bribery and indoctrination. Because leaders can pick and choose which coup-proofing measures to employ, leaders facing coup and belligerent adversary threats can reduce the coup-proofing dilemma by adopting those coup-proofing measures that do not reduce effectiveness and avoiding those measures that reduce effectiveness, within availability and dependence constraints. The paper presents a case study of coup-proofing in Nazi Germany, a deviant case for coup-proofing theory and democratic victory theory because Adolf Hitler avoided being overthrown in a coup and fielded an effective military. The case study demonstrates support for the theory that a leader can simultaneously reduce coup risk and optimize military effectiveness by employing some coup-proofing tactics but not others.