Institutional accountability is central to democratic governance, yet philosophical inquiry still lacks a conceptually refined and comprehensive map to appreciate its boundaries and defining features. This article offers such a map from a human‐centered view of institutional action. Institutions are not merely systems of rules and procedures; they are enacted through officeholders' interdependent and relatively discretionary conduct‐in‐role. Accountability, therefore, must be understood not only as a mechanism but also as a lived practice internal to office‐based action. The article develops a three‐tier taxonomy. First, it distinguishes the agents of institutional accountability—individual officeholders or institutional collectives—showing how this axis intersects, without collapsing, into vertical and horizontal relations. Second, it delineates two different but potentially integrated modes of institutional accountability: “answerability,” grounded in oversight, assessment, and potential sanctions, and “addressability,” grounded in reciprocal reason‐giving, mutuality, and co‐authorship. Third, it identifies the implications of accountability for institutional functioning, distinguishing between practices of correction and those cultivating cooperation. The resulting framework offers both an analytical vocabulary for accountability studies and a conceptual refinement of accountability suited to humanly enacted institutions.