Trance and Treatment was written as an introduction for someone new to the subject of hypnosis, but also includes material in sufficient depth so that therapists with wide experience in the field can acquire new perspectives. Our approach differs from the current clinical literature in emphasising the importance of performing a systematic assessment of hypnotisability; the method is described in detail along with data relating performance on the Hypnotic Induction Profile to personality style, psychopathology, and treatment outcome.