The concept of software product is often associated to software code; process documents are, therefore, considered as by-products. Also very frequently, customers primarily demand "results" and, in a second place, documentation. Development efforts are then focused on code production at the expense of documents quality and corresponding verification activities. As discussed within this paper, one of the root problems for this is that documentation in the context of methodologies is often described with not enough level of detail. This paper presents a metamodel that faces this problem. It is an extension of ISO/IEC 24744, the metamodel for methodologies development. Under this extension, documents can become the drivers of the methodology activities. Documents will be the artifact in which method engineers should focus for methodology development, by defining its structure and constraints. Developers will put their effort in filling sections of the documents as the way to progress in the process execution. This process execution will be guided by those documents defined by the method engineers. This approach can be, as well, the basis for a new approach to a Document-Centric Software Engineering Environment.