The article discusses the growing interest in cultural-historical activity theory (CHAT) and its potential to promote change in work and educational practices through research interventions. Seeds for research interventions in CHAT are identified in the rich heritage of the works of Vygotsky and other classic authors. Particular attention is devoted to Vygotsky's epistemic reasoning in "The Historical Meaning of the Crisis in Psychology" and to his emphasis on the use of an indirect method in psychological investigations. In "The Historical Meaning of the Crisis in Psychology," Vygotsky formulated a program for the development of psychological theory and methodology. The article points out that the future of activity theory depends on the understanding and creative development of this heritage. On this basis, interventionism is presented as a central aspect in CHAT. Historical and theoretical foundations of CHAT are connected to current methodological implementations of interventionist research such as the Change Laboratory, the Clinic of Activity, and the Fifth Dimension.
Based on critical readings of the three main contributions of the special issue and on my own research experiences, the article points out three related features of developmental activity research projects as particularly challenging for the analysis and advancement of cultural-historical activity theory (CHAT). One feature is the nature of the joint developmental project. A second feature is the researchers' role in the joint developmental activity. The third feature is the focus on the transformations of the central artifacts that make up the joint project. Finally, with departure from the stance that developmental activity research projects are propelled by two kinds of practitioners-the practitioners of research and the practitioners of another activity-which may support each other not only in practical matters but also with regard to concepts and perspectives, I consider advancement of CHAT methodology by outlining a beyond-interventionist methodology.