As organizations confront the escalating imperatives of Sustainable Development Goal 12 — Responsible consumption and production — Sustainability transitions are often framed as strategic or technological challenges. Yet this narrative review argues that the true battleground lies deeper: within the silent infrastructures that shape organizational behavior. Conceptualizing managerial accounting as behavioral infrastructure, this review repositions accounting systems not as neutral measurement tools, but as active cognitive, motivational, and normative architectures that scaffold — or undermine — Sustainability practices. Through a critical synthesis of contemporary sustainability accounting, behavioral management, and environmental psychology literatures, the review advances four key contributions. First, it reframes budgeting, costing, performance measurement, and internal control systems as behavioral architectures that condition responsible consumption. Second, it illuminates the underexplored mediating role of accounting infrastructures in shaping employee well-being, organizational culture, and ethical engagement. Third, it critiques the field's preoccupation with external disclosure, calling for a methodological shift toward studying internal behavioral dynamics. Fourth, it reimagines managerial accounting as an ethical infrastructure: a latent moral architecture shaping not only ecological outcomes but the dignity and flourishing of organizational life. By exposing the hidden behavioral terrains where sustainability succeeds or fails, this review calls for an urgent reconfiguration of accounting systems — From instruments of compliance to catalysts of transformative organizational change. Managerial accounting, long relegated to the background of sustainability discourse, must be recognized as a decisive frontier in humanity's struggle to live within planetary limits.