GONIN-GUMI
五人組
"Five-man team"
During the Edo period, the head of every household was obliged to join a collective association with four other heads of households. The members of the association were mutually responsible for each other. If one member failed to pay his taxes, the other members of the group would be forced to make up the difference. If one member committed a crime and fled, then his fellows would have to pay compensation.
The objective of the five-man-team was to encourage proper behavior through peer pressure. The practice was resurrected during World War II, when the Japanese government mobilized the nation for the war effort.
Although formal five-man teams no longer exist, the concept of peer pressure as a tool to enforce conformity continues in many institutions in Japan. At work as well as in private life, the threat of haji / 恥, or shame, is enough to keep most people on the straight and narrow.