The seventh international seminar on Vygotsky held in Geneva discussed a new French language translation of texts of from ‘pedology,' the now largely lost Soviet science of the developing child. In this introduction, the guest editors touch on three concepts of development which coincide with the three elements of Vygotsky's best known idea, the Zoped, or zone of proximal development. In each case, we find that Vygotsky's pedological texts has the potential to completely change the way in which we have understood the concept.