For the past few years I have been using past life regression therapy with a great deal of success.
The particular technique that I use is a form of guided visualisation - this is not hypnosis (although the meditative state is very similar to a light hypnotic trance). During this visualisation, I will guide my client to explore memories from their previous lives, and attempt to help them find memories that may have an impact on their current existence.
I have found that, in many people, coming to terms with, and accepting these buried memories may be very beneficial at a very deep level, and can be a great help in assisting us to overcome problems and trauma in our present day lives.
There are innumerable theories and beliefs regarding reincarnation and past lives. Almost every culture throughout history has held some form of belief in rebirth, and some eastern cultures have a vast body of literature on the subject.
There have been a number of carefully researched and documented studies on this subject by some highly respected researchers. No-one can deny that perfectly normal people can, under certain circumstances, recall in great detail memories of episodes from the past. In many cases, these experiences have been checked by reputable historians, who have verified the accuracy of the details. In some of these instances, the memories have been of events that were so obscure, that it was found to be very unlikely that anyone other than a historian or archeologist could have known them.
I reserve judgement as to whether these memories are proof of reincarnation, or are caused by some other phenomena such as perhaps some form of "Genetic Memory" (Biologists have found that our DNA is capable of storing huge amounts of information), or something along the lines of Jung's "Collective Unconscious", or even by some weird property of time and space, that we do not yet understand. What I do know is that the phenomenum is very real, and can provide great benefits to a person who is trying to get to grips with their present life...