Over the course of her career Sylvia Scribner made numerous contributions to our understanding of how human activity is related to psychological functioning. Her focus on activity is most explicit in the ingenious analyses she conducted near the end of her career on cognitive processes in the workplace, analyses that were specifically grounded in the theory of activity outlined by Leont'ev (1981) and others. In our view, however, Scribner made major contributions to what may be termed an activity oriented approach to psychology even before she began explicitly grounding her claims in the writings of activity theorists. For example, her decades of work on the relationship between literacy and psychological processes are perhaps best understood in terms of what she and her colleagues came to call a “practice account of literacy” (Scribner & Cole 1981, p. 235). This and other earlier research concerned with literacy, language, and thought focused consistently on how “socially organized activities may come to have consequences for human thought” (p. 235). In one way or another, then, much of Scribner's research can be viewed as being grounded in the assumption that the study of human mental functioning is best approached from the perspective of socioculturally situated activity.

In an attempt to explicate the forms of activity Scribner considered in her studies of literacy we shall harness the notion of “mediated action” (Wertsch 1991; Zinchenko 1985). Our use of this notion reflects the intellectual heritage we share with Scribner, a heritage grounded in the works of authors such as Vygotsky (1977, 1978, 1981, 1987), Leont'ev (1981), Tulviste (1991), and Zinchenko (1985).