This part of IEC 62559 “Use case methodology” defines the structure of a use case template, template lists for actors and requirements, as well as their relation to each other. In this document, a standardized template for the description of use cases is defined for various purposes like the use in standardization organizations for standards development or within development projects for system development. This document was developed for general application in various domains and systems. The energy system/smart grid is used as example in this document as it was one of the first usage areas for this use case template, but this general template can be applied in other usage areas different from energy systems as well (e.g. smart home or electro-mobility). The motivation, background information on use cases, recommendations for the handling of use cases and the processes for the description of use cases inside standardization and in relation to a central use case repository is described in IEC 62559-1.