Use cases are a foundational element of most system design and development methodologies. The XSEDE system integration team defines and references its intended user experiences through use cases. In XSEDE, use cases enable people from many backgrounds and disciplines to speak coherently with each other about XSEDE's capabilities and proposed changes to the system. With use cases as an organizing principle, XSEDE has built an open and transparent framework in which researchers, software developers, and service providers can view the system's intended user experiences, the implementation activities aimed at delivering those experiences, and the resulting system. Use cases are one of several metrics used by the XSEDE project to continuously measure and track our value to the community. In section 1, we explain why the XSEDE project tracks use cases and the benefits this provides. In section 2, we describe the methods XSEDE follows for defining and tracking use cases. In section 3, we describe the tools XSEDE uses to manage use cases.