Iaido is a modern Japanese martial art and sport that emphasizes being aware and capable of quickly drawing the sword and responding to a sudden attack.

Iaido, in its modern form, is practiced as a competitive sport. The competition consists of two iaidoka performing their kata next to each other and simultaneously. The competitors will be judged by a panel of judges according to the standardized regulations.

Iaido is associated with the smooth, controlled movements of drawing the sword from its scabbard (or saya), striking or cutting an opponent, removing blood from the blade, and then replacing the sword in the scabbard. While beginning practitioners of iaido may start learning with a wooden sword (bokken) depending on the teaching style of a particular instructor, most of the practitioners use the blunt edged sword, called iaitō. Few, more experienced, iaido practitioners use a sharp edged sword (shinken).