ABSTRACT
In this publication from the turn of the century I explain why I felt a new concept was needed within sociocultural theory (which I also refer to as CHAT, Cultural Historical Activity Theory) that was more social, and more dialogic, than Vygotsky’s ‘Zone of Proximal Development’. My proposal was the concept of the ‘Intermental Development Zone’, which I hoped would help create a theoretical link between conversational interaction and individual learning. The ‘Talk Lessons’ programme I refer to later in the chapter is what has become better known as ‘Thinking Together’ (https://thinkingtogether.educ.cam.ac.uk).
