One-on-One Tutoring by Humans and Computers articulates the CIRCSIM-Tutor project, an attempt to develop a computer tutor that generates a natural language dialogue with a student. Editors Martha Evens and Joel Michael present the educational context within which the project was launched, as well as research into tutoring, the process of implementation of CIRCSIM-Tutor, and the results of using CIRCSIM-Tutor in the classroom. The domain of this project is cardiovascular physiology, specifically targeting first-year medical students, though the idea is applicable to the development of...