The Technological Innovations in Medical Education (TIME) Project has created an interactive videodisc patient-simulation model that provides faculty with a new method for patient-centered teaching in the medical school classroom. The TIME model is designed to be controlled by a professor in the classroom setting, and incorporates voice recognition technology and video dramatization to create a believable patient encounter. Under the auspices of the Lister Hill National Center for Biomedical Communications, National Library of Medicine, where the Project originated in 1983, three medical schools participated in a field test of this "high-tech" model. Six faculty members made ten classroom presentations of two TIME simulations to 306 second-year medical students. The principal finding was that, in a group setting, a large majority of the students at all three schools became individually committed to the care and management of the simulated patient. They acted as if the patient's problems were real and left the session feeling as though they had interacted with an actual person. Therefore, in terms of simulating a real patient, the TIME patient-simulation model was validated, providing the basis for the development of new patient-centered methods to teach and test medical students in the classroom setting. The Project has been at the Georgetown University School of Medicine, where the model is being introduced into the existing curriculum, since 1988. It is currently being used as a part of the final examination for second-year students and in discussion-group settings for fourth-year students in the internal medicine clerkship. A field test is also under way using the TIME model to assess the clinical performance of third-year students.