This thesis takes as the object of its enquiry children's talk about the range of different media texts which they circulate amongst themselves in informal settings. It uses this data to raise questions about how we can conceptualise literacy in a multimedia age; the role that talk about texts plays in establishing what it means to read and to be a reader; and the relationship between talk, text and context. The thesis contributes to the development of a social theory of literacy by linking differences observed in ways of talking about texts to different aspects of the social contexts in which those texts circulate. It redefines the social contexts for reading which shape a given literacy event in terms of the social processes through which texts are made available to particular readers ii. particular settings. These social processes are described in terms of the social regulation of texts. The methodological and theoretical issues the thesis tackles arise largely from the attempt to construct a new language of description (See Bernstein, 1996) for the range of talk about texts collected as part of the research data. The language used to describe the data has become the means for making visible aspects of literacy as a social practice which have been previously overlooked. In this respect, the act of description is therefore in itself theoretical: it helps formulate what it refers to.