Dr. William Menninger summarizes what he considers to be the basic principles of psychiatry necessary for the practice of good, scientific, comprehensive medicine. In order for the physician to treat the patient as a whole and not as a collection of separate organs and functions, he must accept the concept of personality, its anatomy, physiology, development and pathology. The physician must respect the role of the environment, the importance of interpersonal relationships, and the secondary gains involved in all illnesses. Every physician, whether he knows it or not, uses psychotherapy. It is important therefore that all physicians and medical students be well grounded in the basic concepts of psychiatry.