The Bingo Book (手配書, Bingo-Bukku) is a book that contains any and all information on every missing-nin, which all Jonin and members of ANBU of the major shinobi villages are given by their respective Kage to hunt down and assassinate. The purpose of this is so that the village's secrets and/or kekkei genkai aren't stolen or examined by the enemy. Kirigakure has a special unit within their ANBU called hunter-nin, whose sole purpose is the complete eradication of these missing-nin.
There are many versions of the Bingo Book besides those distributed in the shinobi villages. Akatsuki uses a Bingo Book that, instead of listing missing-nin, provides information on the hosts of tailed beasts (which must be captured alive) and those shinobi that are known as the most powerful assets to a certain village. Kakuzu made use of this addition to track down shinobi in the hopes of gaining their bounties, such as when he attempted to kill Asuma for his 35 million ryō bounty.
There are many versions of the Bingo Book besides those distributed in the shinobi villages. Akatsuki uses a Bingo Book that, instead of listing missing-nin, provides information on the hosts of tailed beasts (which must be captured alive) and those shinobi that are known as the most powerful assets to a certain village. Kakuzu made use of this addition to track down shinobi in the hopes of gaining their bounties, such as when he attempted to kill Asuma for his 35 million ryō bounty.
