Hypnosis is a state of focused concentration during which a person becomes less aware of his or her surroundings. Hypnotherapy is the use of hypnosis to treat physical or psychological conditions.

It is thought that during a hypnotic state, or trance, people have a heightened ability to accept suggestions that can help change their behavior. Hypnosis can be led by a hypnotherapist, or a hypnotherapist can teach people to hypnotize themselves (self-hypnosis). Self-hypnosis can also be learned from books.

Self-hypnosis usually consists of writing or adapting a script to induce hypnosis (including suggestions to help with specific problems), recording the script, and playing the tape to induce a hypnotic state. Some people are more comfortable with self-hypnosis because they are alone throughout the exercise and are in control of all suggestions made during the hypnotic trance.

Self-hypnosis is considered safe, even when done by inexperienced people. There are no reported cases of harm resulting from self-hypnosis. However, do not perform self-hypnosis while driving a vehicle or in any situation where you need to be fully alert or able to respond quickly (for example, while operating machinery or while supervising children).