Many computer systems are designed according to engineering and technology principles and are typically difficult to learn and use. The fields of human-computer interaction, interface design, and human factors have made significant contributions to ease of use and are primarily concerned with the interfaces between systems and users, not with the structures that are often more fundamental for designing truly human-centered systems. The emerging paradigm of human-centered computing (HCC)-which has taken many forms-offers a new look at system design. HCC requires more than merely designing an artificial agent to supplement a human agent. The dynamic interactions in a distributed system composed of human and artificial agents-and the context in which the system is situated-are indispensable factors. While we have successfully applied our methodology in designing a prototype of a human-centered intelligent flight-surgeon console at NASA Johnson Space Center, this article presents a methodology for designing human-centered computing systems using electronic medical records (EMR) systems.