Activity-Centered Design

Activity-centered design doesn't focus on the goals and preferences of users, but instead on activities. Activities can be loosely defined as a cluster of actions and decisions that are done for a purpose. Activities can be brief and simple (making a sandwich) or time consuming and involved (learning a foreign language). Activities can take moments or years. You can do them alone or with others, as is the case, for example, when you sing a song. Some activities, such as withdrawing money from an ATM, have a set endingin this case, getting the money. Others, such as listening to music, have no fixed ending. The activity simply stops when the actor (or some outside force) decides it is over.

Many products we use today were designed using activity-centered design, especially functional tools like appliances and cars. Activity-centered design allows designers to tightly focus on the work at hand and create support for the activity itself instead of more distant goals (Figure 2.2). Thus, it's well-suited for complicated actions.

Figure 2.2. A cello is a product designed for one specific activity: making music.

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The purpose of an activity is not necessarily a goal. Purposes are generally more focused and tangible than goals. Consider the activity of raking leaves, for example. The gardener may have a goal (to have a tidy yard), but the purpose of using a rake is simple: to collect leaves.

Of course, sometimes goals and purposes can be the same or similar. For example, in the activity of making tea, the goal and the purpose are pretty much the same: to drink tea. Few people have as a goal to become a master tea brewer.

Activities are made up of actions and decisions. Designers call these tasks. Tasks can be as discrete as pushing a button or as complicated as performing all the steps necessary to launch a nuclear missile. The purpose of tasks is to engage in (and possibly complete) an activity. Each task is a moment in the life of the activity. Consider the simple activity of buying a new game for a game console. Here are the tasks:

• Decide to buy a new game.

• Decide what game to buy.

• Decide where to buy it.

• Get directions to store if necessary.

• Go to store.

• Enter store.

• Find game in store.

• Buy game.

• Leave store.

• Go home.

As this example shows, the difference between a task and an activity can be fairly minor. Some tasks have enough parts to them to be considered subactivities unto themselves. For example, in making a phone call, one of the tasks is finding the right number to dial. There are quite a few ways to find a phone number: call a service for assistance, look up the number in a phone book, recall the number from memory, and so on. Each of these solutions to the task of finding a number is itself a task. So is finding a phone number a task or an activity? For designers, the difference is usually academic.

Like user-centered design, activity-centered design relies on research as the basis for its insights, albeit not as heavily. Designers observe and interview users for insights about their behavior more than about their goals. Designers catalog users' activities and tasks, perhaps add some missing tasks, and then design solutions to help users accomplish the task, not achieve a goal per se.

Ultimately, activity-centered design allows designers to focus narrowly on the tasks at hand and design products and services that support those tasks. The task "submit form" will probably require a button. The task "turn device on" will probably require a switch. And so on. The activity, not the people doing the activity, guides the design.

Activity-centered design can be ethically tricky. Some tasks require skillsometimes great skilland designers shouldn't ignore this in designing alternatives. Removing or automating people's valuable skills can be morally troubling. It may take weeks to learn a call-center's software, for instance. But then again, perhaps the reason the software takes weeks to learn is because it's poorly designed. Designers should be especially careful in choosing the tasks they automate; it is very easy to de-skill users, to remove tasks that may be tedious or difficult to learn, but are also pleasurable to perform. Imagine being asked to design a piano that was easier to learn and play! We'll talk more about ethics and design in the epilogue, "Designing for Good."

Another danger in activity-centered design is that by fixating on tasks, designers won't look for solutions for the problem as a whole. They won't see the forest for the trees. There's an old design adage: You'll get a different result if you tell people to design a vase than if you tell them to design something to hold flowers. By focusing on small tasks, designers can find themselves designing vase after vase and never a hanging garden.