The ecological approach in psychology try to account for the natural complexity of behavior as well as the properties of the environment and the ongoing interaction withe environment. According to this vision, cognitive processes are analyzed as relations between agents and other systems. As noted by Greeno (Greeno, 1998),

paradigmatic situations in this research include people communicating with each other as they plan and evaluate their activities and coordinate their interactions with each other and with material and technological systems In particular the research focuses on interactive systems of activity in which individuals participate, usually to achieve objectives that are meaningful in relation to their more general identities and memberships in communities of practice (pp. 5-6).

This vision is also the core of the Activity Theory. According to this theory basic unit of analysis of all human experience is "activity", a broader concept than individual goal-oriented actions (Leontjev, 1981; Vygotsky, 1978). An activity is undertaken by a human actor motivated towards an object and mediated by a tool (also called artifact).

I should read Lucy A. Suchman (1987) Plans and situated actions: the problem of human-machine communication, Cambridge University Press, New York, NY.