Conceptual change is commonplace in political theory. Recent scholarship argues that improving a concept, or “engineering” it, can sharpen its normative and explanatory power. This article illustrates what political theory can learn from conceptual engineering (CE) by examining the evolution of “corruption” as a case study. Traditionally defined as the “use of entrusted power for private gain,” corruption has been revisited to capture broader institutional dysfunctions. We show how the recent re‐engineering of corruption as a “deficit of office accountability” enhances the concept's ability to capture uses of office power that may undercut institutional functioning beyond illegal acts, including individual wrongdoing and faulty institutional design. Re‐engineering corruption has normative value insofar as it helps policymakers and scholars alike to identify and address questionable uses of office power—including in nondemocratic regimes and nonpublic organizations. The article thereby argues that CE can enhance political theory's methodological toolkit and corroborate its practical relevance.