The human mind has three recording areas or functions: the conscious, the preconscious, and the subconscious or unconscious. The conscious mind records input from whatever sense or combination of senses is focused upon at a given time. The preconscious mind stores facts and experiences formerly the subject of conscious attention and keeps them available for recall under the proper stimuli. The subconscious mind receives and stores (1) threatening memories directly from the censor; (2) old, unused memories from the preconscious; and (3) all stimuli directly from each of the five senses. Hypnosis can be used to relax the mind and release it from barriers to recall, thus facilitating the drawing forth of memories from the subconscious. The subject, however, cannot be compelled to say or do anything contrary to his/her will and can also consciously lie. For this reason, the courts have refused to allow a witness to testify while under hypnosis, nor can information obtained under hypnosis be admitted as evidence. Still, the courts do not object to the use of hypnosis as an investigatory tool which may aid in the obtaining of information and evidence that is admissible in court. Hypnosis can never be a substitute for thorough investigative procedures. It should only be used when all other investigative procedures have been exhausted, and the investigator has reason to believe a witness has information locked away because of some impairment or mental block. Guidelines for the effective use of forensic hypnosis are appended, along with annotations of relevant court cases. A total of 28 bibliographic listings are provided.