The model under discussion was elaborated in response to our need to construct a general, explicit and integrative framework for the seemingly different strands of research that we and our associates have carried out in the last decade or so. The findings of these studies made it increasingly clear to us that it is impossible to account for the dramatic changes in language knowledge and language use in children and adolescents within the boundaries of current research paradigms in language acquisition. Our goal was thus to relate later language acquisition and children's increasing cognitive abilities to literacy development in a motivated way, focusing on germane themes in socio-linguistics and discourse analysis, on the one hand, and facets of written language, on the other.