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Activity Theory and Human-Computer Interaction
Bonnie A. Nardi
What is activity theory, and how will it benefit studies of human-computer interaction? This book
addresses these questions. Many HCI researchers are eager to move beyond the confines of traditional
cognitive science, but it is not clear exactly which direction to move in. This book explores one alternative
for HCI research: activity theory, a research framework and set of perspectives originating in Soviet
psychology in the 1920s. Just as HCI research is concerned with practical problems of design and
evaluation, activity theorists from the outset have addressed practical needs, applying their research efforts
to the problems of mentally and physically handicapped children, educational testing, ergonomics, and
other areas. Following the lead of dialectical materialism, activity theory focuses on practice, which
obviates the need to distinguish ``applied'' from ``pure'' science—understanding everyday practice in the
real world is the very objective of scientific practice.
Activity theory is a powerful and clarifying descriptive tool rather than a strongly predictive
theory. The object of activity theory is to understand the unity of consciousness and activity. Activity
theory incorporates strong notions of intentionality, history, mediation, collaboration and development in
constructing consciousness (see Kaptelinin, chapter 5; Kuutti, this volume). Activity theorists argue that
consciousness is not a set of discrete disembodied cognitive acts (decision making, classification,
remembering), and certainly it is not the brain; rather, consciousness is located in everyday practice: you
are what you do. And what you do is firmly and inextricably embedded in the social matrix of which every
person is an organic part. This social matrix is composed of people and artifacts. Artifacts may be physical
tools or sign systems such as human language. Understanding the interpenetration of the individual, other
people, and artifacts in everyday activity is the challenge activity theory has set for itself.
Unlike anthropology, which is also preoccupied with everyday activity, activity theory is
concerned with the development and function of individual consciousness. Activity theory was developed
by psychologists, so this is not surprising, but it is a very different flavor of psychology from what the West
has been accustomed to, as activity theory emphasizes naturalistic study, culture, and history.
The chapters in part I explain what activity theory is. They, along with the seminal article, ``The
Problem of Activity in Psychology'' by the Russian psychologist Leont'ev (1974) (widely available in
English in university libraries), form a primer of activity theory.
Activity theory offers a set of perspectives on human activity and a set of concepts for describing
that activity. This, it seems to me, is exactly what HCI research needs as we struggle to understand and
describe ``context,'' ``situation,'' ``practice.'' We have recognized that technology use is not a mechanical
input-output relation between a person and a machine; a much richer depiction of the user's situation is
needed for design and evaluation. However, it is unclear how to formulate that depiction in a way that is
not purely ad hoc. Here is where activity theory helps: by providing orienting concepts and perspectives.
As Engeström (1993) has noted, activity theory does not offer ``ready-made techniques and procedures'' for
research; rather, its conceptual tools must be ``concretized according to the specific nature of the object
under scrutiny.''
As we expand our horizons to think not only about usable systems but now useful systems, it is
imperative that we have ways of finding out what would be useful. How can we begin to understand the
best ways to undertake major design projects, such as providing universal access to the Internet, effectively
using computers in the classroom, supporting distributed work teams, and even promoting international
understanding in ways both small (e.g., international video/e-mail pen-pals for schoolchildren) and large
(e.g., using technology to find new means of conflict resolution)? Laboratory-based usability studies are
part of the solution, but they are best preceded in a phased design process by careful field studies to
ascertain how technology can fit into users' actual social and material environments, the problems users

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have that technology can remedy, the applications that will promote creativity and enlightenment, and how
we can design humane technology that ensures privacy and dignity.
Recently a major American journal of HCI rejected a set of papers that would have formed a
special issue on activity theory. The concern was that activity theory is hard to learn, and because we have
not seen its actual benefits realized in specific empirical studies, the time spent learning it would be of
dubious benefit. The chapters in parts II and III of this book speak to this concern by providing empirical
studies of human-computer interaction developed from an activity theory perspective. In these pages you
will meet Danish homicide detectives, a beleaguered U.S. Post Office robot and its human creators,
disgruntled slide makers, absent-minded professors, enthusiastic elementary school students, sly college
students, and others. These people and artifacts, and the situations in which they are embedded, are
analyzed with concepts from activity theory. Several interesting ways to structure an activity theory
analysis are provided in these chapters, so readers are offered substantial methodological tools to support
practice.
Throughout the book we have tried to ``compare and contrast'' activity theory with other
techniques and theories to make it ``easier'' to learn (if indeed it is truly difficult). Thus readers will find
that as they read the chapters, they may think about activity theory in relation to cognitive science, GOMS,
Gibson's work on affordances, Norman's cognitive artifacts, situated action models, distributed cognition,
actor-network theory, and other social scientific artifacts. Bannon and Bødker (1991) have compared
activity theory to task analysis and user modeling elsewhere, so we have not undertaken that task here.
Briefly, they argued that these approaches are very limited in that (1) task analysis provides a set of
procedural steps by which a task supposedly proceeds, with little attention to ``the tacit knowledge that is
required in many skilled activities, or the fluent action in the actual work process,'' and (2) user modeling
considers user characteristics (e.g., is the user an expert or a novice?) but says little about the situation in
which the user works or the nature of the work itself.
Activity theory proposes a strong notion of mediation—all human experience is shaped by the
tools and sign systems we use. Mediators connect us organically and intimately to the world; they are not
merely filters or channels through which experience is carried, like water in a pipe (see Zinchenko, this
volume). Activity theorists are the first to note that activity theory itself is but one mediating tool for
research (as are all theories!) and that like any tool, its design evolves over time (see Kaptelinin, chapter 3,
this volume). Activity theory is certainly evolving and growing; it is not by any means a static end point.
Activity theory has a tremendous capacity for growth and change, an intellectual energy that is
being realized in research efforts in Russia, Europe, North America, and Australia. I think perhaps this is
because of activity theory's rich philosophical and scientific heritage and because it permits such wide
scope of analysis. Activity theory provides ample room in the intellectual sandbox for adventure and
discovery and leads to the work of philosophers, psychologists, anthropologists, linguists, educators, and
others whose thoughts have influenced activity theory. The chapters in part III of this book push on the
frontiers of activity theory, expanding its conceptual base.
Let's talk for a moment about the most concrete practical benefit we could expect from activity
theory in the near term. The most immediate benefit I hope for is the dissemination of a common
vocabulary for describing activity that all HCI researchers would share. Activity theory has a simple but
powerful hierarchy for describing activity that could be common coin for all HCI researchers. This
hierarchy (described in several of the chapters in this book) has a superficial resemblance to GOMS but
goes beyond GOMS in essential ways, especially in describing dynamic movement between levels of
activity rather than assuming stasis.
The development of a common vocabulary is crucial for HCI. As we move toward ethnographic
and participatory design methods to discover and describe real everyday activity, we run into the problem
that has bedeviled anthropology for so long: every account is an ad hoc description cast in situationally
specific terms. Abstraction, generalization and comparison become problematic. An ethnographic
description, although it may contain much information of direct value for design and evaluation, remains a
narrative account structured according to the author's own personal vocabulary, largely unconstrained and
arbitrary. Ethnography—literally, ``writing culture''—assumes no a priori framework that orders the data,
that contributes to the coherence and generalizability of the descriptive account. This leads to a
disappointing lack of cumulative research results. One would like to be able to develop a comparative
framework, perhaps a taxonomy as suggested by Brooks (1991), that would help us as we pursue design
and evaluation activities. It would be desirable to be able to go back to previous work and find a structured