The user-centered approach is central to the creation of usable information systems, services, and institutions. Information system design should derive from user research into information needs, tasks accomplished in meeting those needs, and resources used in the tasks. "Information Tasks" summarizes user research, then presents design sketches of systems that illustrate how design is linked to research. Also discussed are usable information services and an overview of the organization and economics of information institutions. This comprehensive user-centered approach provides an agenda for...