Menkyo

 is a Japanese term meaning "license." It refers to the license to teach used by practitioners of various Japanese classical arts and martial arts certifying some license within the school or ryū. The "menkyo" system dates back to the 8th century.
Koryū Tradition.
Although it is most commonly thought to be used for classical martial arts and ways, it can also be used for other arts such as painting ("sumi-e"), tea ceremony ("chadō"), flower arranging or calligraphy ("shodō").
Different martial art "ko-ryū" use different license; one outline is:
Menkyo Kaiden.
, (めんきょかいでん) is a Japanese term meaning "license of total transmission." means "initiation into an art or discipline." It is a license that is used by a school or "ko-ryū", meaning that the student has learned everything and passed all aspects of his/her training within the ko-ryū.
In the "menkyo" system of licenses, the "menkyo kaiden" is the highest level of license that exists under the "menkyo" system. Advancement of license is not determined by years spent learning, but how well one masters the discipline. However, the transition from "menkyo" to "kaiden" require usually at least thirty years' experience. A holder of "menkyo kaiden" is often, but not always, the de facto successor to the "sōke" of the "koryū".