Wikipedia
In the history of Korea Hyangyak was a contractual arrangement that allowed for a degree of local government.
During the rule of Jungjong (1506–1544), this contract was enforced by the local level officials; specific details were circulated in text and operated as an informal common law. The hyangyak became the core of Korea's social law and the vehicle of a degree of local autonomy for its villages.
This was a stepping stone for the Joseon Dynasty in implementing government at the local level. Local yangban, or Korean scholar-officials were lifted in importance because of the role they played. The implementation of the hyangyak opened the way for schools and shrines and tied the yangban to the community as instrumental in strengthening the government at all levels.