Infrastructure is the foundation of every digital experience, and this places the broader charter of service design on the infrastructure and operations (I&O) team. I&O leaders must own the design for the full system of interacting parts sourced from a rich and dynamic software-defined ecosystem. Forrester's infrastructure transformation playbook, with its discover, plan, and act phases, provides the blueprint that I&O leaders and their teams need to meet this challenge. This is an update of a previously published report; Forrester reviews and revises it periodically for continued relevance and accuracy.