Dai Ko Myo is the fourth and the last step of the 4 main levels of Reiki. Dai Ko Myo means 'master'. Its use is possible only if a person has passed to the 4th level of Reiki and has all the skills of a healer. In Japan, it is issued only together with a certificate. It is impossible to use this symbol up to this stage, otherwise the patient can cause significant harm.
