Baruch B. Schwarz is the Isadore and Bertha Gudelsky Chair of Early Childhood Education at the Hebrew University of Jerusalem. His research includes various domains such as mathematical abstraction, or collaborative learning, but his main interest focuses on the study of argumentation in learning contexts. He has extensively published on this topic and has co-created the Special Group Interest in Argumentation, Reasoning and Dialogue at the European Association for Research in Learning and Instruction. He has shown the crucial role of technologies in boosting collaborative learning and argumentation, and has coordinated numerous multi-national EC funded projects dedicated to computer-supported collaborative learning and argumentation. Michael J. Baker is a Research Director (tenured Research Professor) of the CNRS, the French National Centre for Scientific Research, working in the Social and Economic Sciences Department of Telecom ParisTech, the French National Telecommunications Engineering School. His interdisciplinary research in psychology and language sciences aims to understand the processes of knowledge co-elaboration in dialogues produced in educational and work situations, mostly involving technological mediation, focusing on argumentative interactions. In collaboration with Baruch Schwarz and Jerry Andriessen, he has contributed to and co-edited several books on this topic.