Firstly ‘Iai’-'Do’ is the more sporty version. ‘Iai’-'Jutsu’ is the less sporty, killing version. Basically both are Iai, the meditative art of taking off a head, or arm so fast the strike cannot be seen or stopped. In one sense it is arguably the most lethal of all weapon arts. (So long as one does not consider advanced gun use to be a martial art).
As an example Muso Jikiden Eishin Ryu uses the word Iaido. As does Zen Iaido Renmei
‘Do’ can mean ‘one way’. ‘Jutsu’ is different routes.

Iai roughly means ‘being in place.

In Iai there are basic katas, some of which are started from a seated position. Admittedly, as most uses of Iai would, arguably be more applicable from a standing position, the seated kata set, in one sense, is out of date in a western context.
The sword is generally in the upright, non combative position, and is turned as part of the strike preparation.
ORDER
1 One draws.
2 One strikes, often with a light disruptive cut, then a killing second cut.
3 one flicks blood off the sword with a sweeping motion.
4 one sheathes sword.
Steps are in a flowing, smooth sequence. To strike so fast as to be unseen is the goal.

As Mushasi was to duelling, so Master Koto was perhaps the greatest of all Iai artists.

Iai do or Jutsu is practised between skilled artists. To be fast in Iaijutsu is to refine the self. One must be both of ego, to believe in victory with no doubt or slowness of reaction time, but to be humble when confronted with mistakes.

Iai was the first art to teach ‘no mind’ principles.

Mark Alexander
Junior of ‘master killing sword’

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