Value is the structural construct through which a unit makes its Purpose observable and verifiable in its environment. It defines what is delivered, how it is interpreted, and why it matters to external entities. Without Value, Purpose remains inert and Function becomes unjustified, leaving the unit unable to establish relevance, legitimacy, or coordination. In Purpose Driven Design, Value is not an internal output but an externally interpretable offering—expressed as products, services, experiences, or by-products. This chapter establishes Value as a design surface that anchors interaction, enables composability, and provides the basis for trust, accountability, and adaptation in sociotechnical systems.