FUSE (Formal User Interface Specification Environment) is an integrated user interface development environment that offers tool-based support for all phases of the interface design process. PLUG-IN forms one part of FUSE. Its purpose is to provide support for the end-user working with user interfaces generated by FUSE. PLUG-IN produces dynamic on-line help pages and animation sequences on the fly. On the dynamic help pages textual help for the user is displayed whereas the animation sequences are used to show how the user can interact with the application. In the presentation the architecture of FUSE is discussed. Furthermore PLUG-IN’s user guidance capabilities are demonstrated by looking at the user interface of an interactive ISDN telephone simulation. Keywords Intelligent user interfaces, model-based user interface design, user guidance, generated on-line help systems