: The use of program generation from graphical representations like UML is increasing in software projects. The notion of hypergenericity is raising up to improve program generators. This paper presents MetaScribe, a tool designed to build program generators providing guidelines to program generator designers and having enhanced facilities for reusability. An example illustrates the use of MetaScribe: the construction of program generators from UML Class diagrams to C++ and Ada95. Key word: Prototyping, Meta-data description, Semantic transformation, Program generation, Hypergenericity.