Activity-centered design (ACD), which is an approach to interaction design, does not focus on the goals and preferences of the user, but on the activity a user would perform with a given piece of technology. ACD has its theoretical underpinnings in Activity Theory[1], from which activities can be defined as actions taken by a user to achieve a goal[2].
When working with activity-centered design, the designers use research to get insights of the users. Observations and interviews are typical approaches to learn more about the users behavior. By mapping users' activities and tasks the designer may notice missing tasks for the activity to become more easy to perform, and thus design solutions to accomplish those tasks.
Saffer, Dan. 2010. Designing for interaction.
