Hypnotherapy employs the use of hypnosis—an altered state of consciousness caused by little more than the power of suggestion—to help facilitate behavioral and emotional change. A trained hypnotherapist can cause a trancelike state in clients by using auditory, visual, or other perceptual cues. Once the person enters the hypnotic state, he or she is much more suggestible, making it easier to discuss memories, gain insight, and alter behavior.

Placing persons in a drowsy, sleeplike state in which they allegedly become vulnerable to the suggestions made by the hypnotist. Hypnosis may also be used to tap into the unconscious and is often characterized by vivid recall of memories and fantasies. These properties make hypnosis a useful tool in psychotherapy. Hypnosis also has sinister implications, for subjects may be manipulated to perform embarrassing actions or be susceptible to carrying out the hypnotist's commands after the hypnosis session (posthypnotic suggestion).
Some therapists use hypnosis to recover possibly repressed memories they believe are linked to the person's mental disorder. However, the quality and reliability of information recalled by the patient under hypnosis is not always reliable. Additionally, hypnosis can pose a risk of creating false memories -- usually as a result of unintended suggestions or the asking of leading questions by the therapist. For these reasons, hypnosis is no longer considered a common or mainstream part of most forms of psychotherapy. Also, the use of hypnosis for certain mental disorders in which patients may be highly susceptible to suggestion, such as dissociative disorders, remains especially controversial.
     "Never in my life have I felt so close to peace and to God as I did during your course. You gave me the most fantastic tool anyone could ever find... you taught me to be able to go deep within myself to find the answers and find myself. Now my only objective is to help people with what you have taught me, so they may also find that wonderful world that comes from inside...."
Placing persons in a drowsy, sleeplike state in which they allegedly become vulnerable to the suggestions made by the hypnotist. Hypnosis may also be used to tap into the unconscious and is often characterized by vivid recall of memories and fantasies. These properties make hypnosis a useful tool in psychotherapy. Hypnosis also has sinister implications, for subjects may be manipulated to perform embarrassing actions or be susceptible to carrying out the hypnotist's commands after the hypnosis session (posthypnotic suggestion).
It is far easier to describe what hypnosis is not rather than to describe what it is. For example, it is not one person controlling the mind of another. The patient is not unconscious and does not lose control of his or her faculties. People will not do things under hypnosis that they would be unwilling to do otherwise. The person being hypnotized is always in control. The hypnotized person decides how deep the trance will be, what suggestions will be accepted, and when to awaken. Therefore, a hypnotyized person cannot be forever "lost" if the therapist should fall dead during an induction or while the patient is deep in trance.

It is used for a wide variety of applications, and studies into its efficacy are often of poor quality[2] which makes it difficult to determine efficacy. Several recent meta-analyses and systematic reviews of the literature on various conditions have concluded that the efficacy of hypnotherapy is "not verified",[3] that there is no evidence[4][5] or insufficient evidence[6][7] for efficacy.
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