This document provides a framework for defining key product metrics that enable growth. It discusses organizing metrics in a hierarchy with a focus metric, level 1 metrics that complement the focus metric, and more granular level 2 metrics. It provides examples of common metric categories like reach, activation, engagement, retention, and business-specific metrics. The document also includes examples of metrics frameworks for different industries, like media, e-commerce, and financial services. It discusses how to choose the right metrics based on a company's goals and customize metrics to fit different business models.