Regression as a tool in hypnosis has both supporters and detractors as to whether or not it is a valid practice likely to give accurate results. Those who are proponents of regression believe that a person can recover lost memories of incidents that they have forgotten, sometimes due to traumatic experiences. Some even believe that past lives can be remembered through regression. This of course requires a belief in reincarnation.

Regression has been used by some therapists with adults to recover lost memories of sexual abuse as children. However regression is generally not allowed as evidence in court because the science is still out on whether or not it is usually accurate, and even if usually accurate it has been proven to be not one hundred percent right all of the time. Several court cases in the past twenty years have involved regression to determine whether or not someone suffered sexual abuse as a child. On more than one occasion parents have been convicted of sexual abuse and sent to prison only to be released later when physical evidence proved that it was impossible for them to have been present at the time the abuse was claimed. Many people believe that false memories are created during regression through suggestions planted in the mind of the person undergoing regression by the therapist or others present.

One of the most popular examples of regression today are those who have undergone regression to recover "missing time", memories that they believe were lost when abducted by extraterrestrial aliens. The first example of this was the case of Betty and Barney Hill. The married couple were travelling back home from a vacation when they experienced lost, or missing time. Years later a psychiatrist hypnotized them both and they gave near identical stories of being taken aboard a UFO. Regression has been used by Dr. John Mack, a Harvard physician and by Bud Hopkins, a New York UFO researcher extensively. Both believe that regression is a valid method of recovering lost memories.

Regression may or may not be accurate. No one is totally sure. It could possibly be accurate in the cases of some people at some times, but not with all people one hundred percent of the time. It is unlikely to be allowed in courtroom testimony, but is still one of the most popular research methods used by UFO researchers.