Hypnosis or hypnotism is a psychological phenomenon of exceeding interest to both layman and scientist. Its history is as old as that of the human race, and it has been utilized by the most primitive of peoples, ancient and modern, in the practice of religious and medical rites to intensify belief in mysticism and magic. The striking character of this psychological manifestation, its inexplicable and bewildering phenomenology, and the seemingly miraculous results it produces.together with its long use for the bewilderment of the observer.have served to surround it with an aura of the supernatural and the unreal. As a consequence, the attitude of the general public toward this phenomenon, now scientifically established, has been, and too often still is, one of superstitious awe, misunderstanding, incredulity, antagonism, and actual hostility and fear. This attitude is perpetuated by the exploitation of hypnosis by the charlatan and the stage performer and the well-intentioned but mistaken and inadequate utilization by inexperienced experimenters and medical men. The scientific history of hypnosis began about 1775 with Anton Mesmer, whose name is still attached to it, but unfortunately, even this scientific beginning was founded on a mystical belief that it was constituted of a peculiar cosmic fluid with healing properties. Mesmer.s use of hypnosis began with his discovery that suggestion in various forms could be used to induce a condition resembling sleep in certain types of patients, and that, in this state, therapeutic suggestions could be given to alleviate and even remedy their complaints and symptoms. Unfortunately, Mesmer failed to recognize the purely psychological character of his discovery and attributed it to a cosmic force he termed .animal magnetism.. Although Mesmer successfully treated large numbers of patients on whom orthodox medical procedures had failed, he fell into disrepute because of the mysticism with which he surrounded his therapy. Nevertheless, his discovery and utilization of it served to lay a foundation for the therapeutic use of hypnosis and for a recognition of the validity of psychotherapy as a medical procedure. Since Mesmer’s time there has been a succession of scientific men, chiefly medical, who have contributed greatly to its scientific growth. Elliotson, the first British physician to use a stethoscope, used hypnosis effectively about 1817 in his medical practice and published extensively on its suitability for certain types of patients. Esdaile, through Elliotson’s writings, became so interested that he succeeded in having a government hospital built in India primarily for the use of hypnosis, where he extended its use to all types of patients, especially surgical. In 1841 James Braid, an English physician who bitterly opposed .mesmerism,. was induced to make a physical examination of a mesmerized subject. He recognized both the validity of the phenomenon and its psychological character, with the result that he coined the terms hypnosis and hypnotism and initiated the first scientific studies of hypnosis as a psychological condition of extensive medical and scientific significance. Since then, clinicians first and psychologists later, among them many outstanding scientists, have contributed increasingly to a better understanding and utilization of hypnosis as a scientific tool and as a medical procedure of immense value for certain types of patients. Particularly has interest been developing rapidly during the last 25 years among psychiatrists and psychologists. During the last 15 years there has been an increasing wealth of publications dealing with the effective use of hypnosis in the fields of psychiatry and experimental psychology. Regrettably, however, there is still a persistence of outmoded ideas and concepts of hypnosis which vitiate experimental studies and therapeutic efforts. For example, some psychologists are still publishing studies based upon techniques and psychological concepts belonging to the 19th century, and some medical men still employ it for direct symptom relief rather than as an educative procedure for the correction of personality disorders. As yet the scientific study of hypnosis is still in its infancy despite the development of a healthy, intense interest in it as a scientific problem of merit. There is still lacking an adequate general appreciation of the need to integrate hypnotic studies with our presentday concepts and understandings of personality, of inter- and intrapersonal relationships, and psychosomatic interrelationships and interdependencies.