In a previous attempt to outline the challenges facing cultural-historical activity theory, I observed two opposite tendencies in our field:

This volume is a welcome example of the second tendency. I see it as a formative intervention, a virtual Change Laboratory (Engeström, 2007e), attended by a diverse group of scholars interested in pushing forward the development of activity theory. Looking at this effort through Vygotsky's (1997b) idea of double stimulation, the first stimulus or “problem space” for the contributors was the body of research and theorizing I have produced over the years. The second stimulus consisted of the critical reviews written by other authors and colleagues.

However, the resulting chapters are not merely commentaries on my work. Double stimulation is an expansive method. It pushes the subject to go beyond the problem initially given, to open up and expand on an object behind the problem. In this case, the object is activity theory, embedded in its relations to other theories and to the societal reality it tries to grasp and change.