Mediated Discourse sets out a discursive theory of human action. Language and action are intimately related. The difficult question to answer is how they are related. Mediated Discourse Theory looks into social relationships to see how the use of language is both a form of action in itself and is also indirectly related to all other forms of human action. Through the empirical study of a one-year-old child learning to exchange objects with caregivers, Scollon challenges the claim that all practices are represented in discourse and that all discourse has the function of structuring practice. 1. Mediated Discourse: A Discursive Theory of Human Action 2. On the Ontogenesis of a Social Practice 3. On the Ontogenesis of a Social Actor: From Object to Agency in Baby Talk 4. Objects as Mediational Means: The Crayon Appropriates a Child 5. The Nexus of Practice 6. Mediated Discourse as a Nexus of Practice