The Yakuza is a transnational organized crime syndicate that originated in Japan and has been in existence for more than 300 years. The word Yakuza means "gangster" in English, and they are known for their involvement in a Mafia-like criminal organization. The Yakuza is made up of various gangs, each with its own code and agenda, and they are split into 21 designated crime groups. They have been involved in criminal activities such as international drug-smuggling, human trafficking, arms smuggling, prostitution, gambling, and day-labor contracting.

The Yakuzas hierarchical structure mimics that of the samurai, and they both value obedience and "honor," and use violence to accomplish their goals. The organization is headed by an oyabun or kumichō (family head) who gives orders to his subordinates, the kobun. Members of Yakuza gangs cut their family ties and transfer their loyalty to the gang boss. They refer to each other as family members—fathers and elder and younger brothers.

The Yakuza have a complex organizational structure. There is an overall boss of the syndicate, the kumicho, and directly beneath him are the saiko komon (senior advisor) and so-honbucho (headquarters chief). The second in the chain of command is the wakagashira, who governs several gangs in a region with the help of a fuku-honbucho who is himself responsible for several gangs. The regional gangs themselves are governed by their local boss, the shateigashira.

Although the Yakuza have been involved in criminal activities, they have also been known to help out in times of crisis because of something called the "Ninkyo Code." Its a principle every Yakuza claims to live by, one that forbids them to allow anyone else to suffer. They have been involved in humanitarian aid, and they were among the first on the scene after Japans devastating 2011 Tōhoku earthquake and tsunami.

In recent years, the Yakuzas memberships have reportedly been at an all-time low, and they are starting to let gang members go. With their assets at least partially frozen, the Yakuza just dont have enough money to pay their members.