Hypermedia documents are most often created with a particular presentation environment in mind. This requires the authoring of one document per presentation platform. As pointed out in [3], much implementation effort can be avoided by specifying how the same underlying document can be presented in different environments. A style sheet defines a mapping from a source document to a presentation for it. We discuss the existing use of style sheets as applied to text and discuss their application to the case of hypermedia, and in particular how they need to be extended.