http://en.wikipedia.org/wiki/Brian_Weiss
Weiss advocates the therapeutic benefits of hypnotic regression, noting his belief that many present-life phobias and ailments are rooted in past-life experiences.
Brian Leslie Weiss (born November 6, 1944), M.D., is an American psychiatrist. His research includes reincarnation, past life regression, future-life progression and survival of the human soul after death. Since 1980, Weiss has regressed more than 4,000 patients.
Yes, Dr Brian Weiss is not a Buddhist and does not believe in reincarnation. However, after engaging with thousands of patients, the evidences presented by some of his patients have dumbfounded him and the only way he could explain them is to assert that reincarnation do exist. His body of work is credible by the scientific community althougth he is still not without his critics.