A use case narrative documents a series of events executed for a computer application in relation to a topic and described from the point of view of an actor (see Wikipedia). A conventional approach to use case development specifies a single user. However, the CyberGIS project involves developing a platform that can support groups of users working together. Therefore, the use cases for diverse actor groups are a bit more involved, using diverse frames of reference as appropriate. A use case scenario sets specific assumptions/parameters about a particular use case narrative to further refine the specification of that use case. Use case narratives and scenarios can be grouped by topics, as one needs to start somewhere with a description of a problem.