Missing-nin

are ninja who left their village without the intention of returning, often because they have committed criminal acts or to pursue other personal gains. The ninja village that they are from will often try to track them down and eliminate them. Kirigakure has a special hunter-nin task-force whose only objective is killing traitorous ninja. The ninja organization Akatsuki is composed mostly of S-class missing-nin, except for Nagato and Konan, who are the leaders of Amegakure. Most of the missing-nin throughout the series are antagonists.

Depending on the village leader's decisions, the missing-nin in question may be given leniency. The most prominent example is Sasuke Uchiha, who is not marked for death by the Fifth Hokage, Tsunade, as a favor to Naruto Uzumaki, and is instead to be brought back as a Konohagakure citizen. However, according to Kakashi Hatake, a missing-nin is typically marked for death simply for defecting, and such mercy is rare.

Later, when Sasuke infiltrated Kumogakure and abducted their Jinchūriki, Killer Bee, then attacked the Kage Summit, he lost Tsunade's mercy and the Kages branded him as an international criminal, meaning that he is a missing-nin wanted on a global-scale level.