We investigated the perceptions of 71 internal medicine faculty and residents regarding the diagnostic value of the medical history and other attitudes toward the medical interview. Physicians perceive the medical history as having much higher value in diagnosis than either the physical examination or laboratory/radiography information (mean scores, 5.76, 2.41, and 2.49, respectively). The perceptions of the importance of the physician-patient relationship were significantly correlated with the diagnostic value of the history. There was also a strong relationship between the perceived value of the history and preferences for more skilled interviewing responses, as measured by the Helping Relationship Inventory. Contrary to expectations, the perceptions of residents toward the diagnostic value of the patient's history increased significantly over the course of training (5.00 to 6.00). We conclude that despite the increasing emphasis on diagnostic technology, internal medicine residents and faculty continue to view the patient's history as the preeminent source of diagnostic information. Physician attitudes toward the physician-patient relationship and toward the medical interview may contribute to the diagnostic value of the history.