Abstract
Vygotsky considered that the nature of language is for social communication and that language develops entirely from social interaction. Language serves as a mediating tool for thought. External social speech is internalised through mediation and language in this sense is a tool for mediated learning. Sociocultural theorists have discussed mediation in different ways with an emphasis on oral language. This paper analyzes how mediation through oral language and mediation in the Zone of Proximal Development have been interpreted and draws implications for English language teaching.