Book excerpt: Originally published in 1963, this definitive textbook, written by pioneering Professor William S. Kroger’s, defined and shaped the field of hypnosis for over 20 years after its publication, and remains an authoritative text in its field to this day. Together with his seminars presented in association with the American Society of Clinical Hypnosis, Professor Kroger’s textbook changed the perception of hypnosis from being a novelty to a legitimate and respected medical option, and solidified his reputation as a leader in the field.