The interchange between physicians discussing a patient's case has been mentioned in written history since ancient Greece. From the time of Hippocrates, physicians have been encouraged to seek consultation on difficult cases when they were in doubt. They were urged not to be jealous of one another but to realize their own limitations and to use the knowledge of their colleagues to help. “Nor, among physicians, do those who treat by diet envy those who employ surgery, but they even call each other into consultation and commend one another.” It is clear, however, that there were disagreements in those days: “Physicians who meet in consultation must never quarrel or jeer at one another.” There were also “wretched quarrelsome consultations at the bedside of the patient, with no consultant agreeing with another, fearing he might acknowledge a superior.”

Over the next 25 centuries, consultation has had its ups and downs. Much of what was written had to do with the etiquette and ethics of the interaction. In medieval Europe, little changed from ancient times. Physicians were encouraged to ask colleagues for help if needed and to refrain from criticizing each other in front of non-physicians.

In the fourteenth century, patients were warned against consulting large numbers of doctors because there would be “endless disagreements and different suggestions” and “the patients [would] suffer from lack of care.” The doctor could call in another physician for consultations, but the treatment should be administered by the one knowing the most about the case.