I·ai·dō (居合道), literally "the art of immediate mental presence", is a martial art originating in Japan that uses sword drawing techniques based on Batto Jutsu and Iaijutsu to practice immediate mental awareness.
Some ancient practitioners are credited with making the mental jump from drawing the sword for combat and defense to practicing drawing for the mental and physical benefits it provides. Among them is Lisaza Ienao, the founder of Tenshin Shoden katori Shinto Ryu.
Iaidō practice forms some of the requirements of modern kendo (剣道) and Koryu based kenjutsu (剣術):
Iaidō forms, or kata, are practiced against an imaginary opponent and involve drawing the sword, cutting in one or several directions, removing the blood and sheathing the sword.
Seitei iaidō is the name All Japan Kendo Federation (AJKF, Zen Nippon Kendo Renmei) gave a set of katas amalgamated in the 20th century. Seven such katas were based on, Muso Jikiden Eishin-ryu, Muso Shinden-ryu and Hoki Ryu. Three more were added In 1981, and in 2000 another one was added; The total number of Seitei kate isnow 12..
Dojo that are affiliated with the All Japan Kendo Federation generally begin practice with these twelve "official forms" (seitei-gata). AJKF dojos typically start students on these before going on to teach any classical forms of iaidō that may be included in their curriculum.