Activity theory is an interdisciplinary approach to human sciences that originates in the cultural-historical psychology school, initiated by Vygotsky, Leont'ev, and Luria. It takes the object-oriented, artifact-mediated collective activity system as its unit of analysis, thus bridging the gulf between the individual subject and the societal structure. This 1999 volume includes 26 chapters on activity theory by authors from ten countries. In Part...