Reiki is a form of spiritual practice, used as a complementary therapy, proposed for the treatment of physical, emotional, and mental diseases. Mikao Usui developed Reiki in early 20th century Japan, where he said he received the ability of 'healing without energy depletion after three weeks of fasting and meditating on Mount Kurama. Practitioners use a technique similar to the laying on of hands, which they say will channel "healing energy" (ki). Practitioners state that energy flows through their palms to bring about healing and that the method can be used for self-treatment as well as treatment of others.
The belief is that the energy will flow through the practitioner's hands whenever the hands are placed on, or held near a potential recipient, who can be clothed. Some teachings stress the importance of the practitioner's intention or presence in this process, while others claim that the energy is drawn by the recipient's injury to activate or enhance the natural healing processes. Going further, the belief is that the 'energy' is 'intelligent', making diagnosis unnecessary.
The energy involved in a Reiki treatment is said to be 'from the Universe, rather than the personal energy of the practitioner and is therefore inexhaustible (Some teachings say that the energy enters the practitioner through the crown chakra at the top of the head, before being emitted from the hands). As a consequence, Reiki practitioners are taught that they can treat themselves with Reiki.