As holistic medicine becomes increasingly popular, Reiki is being hailed as a treatment for helping body, mind, and spirit. This makes it very different from traditional allopathic medicine, which typically only addresses the disease itself. The word Rei means "universal," or present everywhere. Research into the esoteric meaning of the word reveals that it is more accurately interpreted to mean "spiritual consciousness" or "supernatural knowledge." This "God-consciousness" is said to be all-knowing, able to see the root of all problems and then heal them.

Other names for ki include Chi, as the Chinese call it, Ti or Ki in Hawaiian, Prana in Sanskrit, orgone, bioplasma, and odic force. Various cultures that recognize its existence have given it many other names. As long as something is alive, ki circulates through it and around it. When ki dies, the life force departs and the organism dies. Ki is also the source from which emotions, thoughts, and spiritual life are drawn. The Chinese have studied ki, or as they call it, "chi," for thousands of years and place great importance on it. One of their classic tomes lists thirty-two different kinds of chi and is over 4,000 years old. Ki is also used by practitioners of the martial arts for mental development and physical training. It is used in Pranayama (meditative breathing exercises) and by shamans in many cultures for divination, psychic awareness, and healing. While Reiki is not a religion, it can be interpreted as a spiritually guided practice. Teachers therefore recommend that practitioners live in accordance with certain ethical ideals and do their best to promote peace and harmony in the world.