Reiki is one of the oldest, more mysterious and lesser known energy systems used in hands-on treatment. It is mysterious because no one can explain exactly how it works; lesser known, because the majority of its practioners are lay people who use it on themselves, friends and family rather than professionally. Although Reiki dramatically enhances the body's own natural healing ability, its treatment of physical disease is considered a wondeful "side effect" only. More important is the expansion of personal awareness that results when Reiki is used on a regular basis.