For the past twenty years we have been studying methods of teaching and their effectiveness in changing the behaviour of medical students and doctors. At the Massachusetts General Hospital our work was concerned primarily with teaching psychotherapy to medical students, residents and younger physicians. During these years we have practised and taught many kinds of psychotherapy, including situational therapy, relationship therapy such as catharsis, support, reassurance, suggestion and persuasion, and the various types of insight therapy from the verbalization and understanding of simple correlations to more extensive Freudian psychoanalysis. The patients we treated in Boston were primarily those with psychoneuroses and psychosomatic disturbances. In these groups of patients insight therapy was the method of choice. It was only when insight therapy was impracticable or too disturbing to the patient that other methods such as relationship therapy were used. During these years we used insight therapy whenever possible, often with limited effectiveness. The treatment for any given hospital admission required from 20 to 40 interviews, occasionally more. It was our practice to use the vis-à-vis interview method.