Traditional localization optimizes for accuracy and turnaround time. That is no longer enough. This white paper lays out Performance Localization, a KPI-driven operating model that aligns language, AI, and workflow engineering with commercial outcomes like conversion, ROAS, and speed to market. It defines the KPI Gap that quietly drains enterprise revenue across cost, speed, and engagement, and shows how leading organizations move localization from a downstream cost center to an upstream revenue engine.