I published a typical ''Hierarchy Of Prototypes'' in a technical paper published around 1987 -- the paper was titled ''Prototyping Toolsets and Methodologies: User/Developer Sociology'' In that paper I distinguished five levels of prototyping: *PaperPrototype *StaticScreens *InteractiveScreens *MixedModeActiveModules *LaboratoryPrototype *FieldPrototype I still think that these are the ''natural'' prototyping levels of fidelity. --RaySchneider ---- CategoryBuildingBlocks