The cultural–historical activity theory (CHAT) is a relatively young theory, but nevertheless it has its history already. Created in the twenties and thirties of the last century in Russia by some psychologists and further developed by their numerous collaborators and students, it became internationally known over several decades – a process that is still going on today. Especially, beginning in the eighties, more and more philosophers, sociologists, psychologists, pedagogues, and others in a growing number of countries became interested in this theory and began to study, to use, and to develop it even further. So, today, we may speak of an inter-disciplinary and international activity-theoretical movement as it presents itself in publications, congresses and conferences, workshops, and unpublished discussions, etc. A look at the development of this theory may serve for a deeper understanding of its fundamentals and potentials. It is the aim of this chapter to make a contribution to the theory by studying its historical development. Of course, in one chapter, it is impossible to show this history in detail. Perhaps, the chapter may stimulate colleagues to describe other aspects of this development and thus promote the theoretical discussion.

First, I give a short description of what is meant by CHAT today. After that, I look back to the beginnings and to the process initiated by the founders of CHAT. Finally, I try to discriminate three stages of this development and argue for the necessity of further development as its fourth stage.