The Yŏngŭijŏng (Korean: 영의정; Hanja: 領議政; pronounced [jʌŋ.ɰi.dʑʌŋ]) or Chief State Councilor was a member of the State Council of Joseon and the highest government position in the Joseon period of Korean history. The Yŏngŭijŏng held roles similar to a modern-day prime minister of a presidential system. As the senior member of the Chief State Council, the Yŏngŭijŏng participated in the administration of general government affairs alongside the Chwaŭijŏng and Uŭijŏng. The title was created in 1400 with the creation of the State Council. Existing for over 500 years, the function was handed over in 1895 during the Kabo Reform to the newly-formed position of the Prime Minister of the Korean Empire. Only one official, usually an elder who had previously served as Chwaŭijŏng, was allowed to assume the position of Yŏngŭijŏng. The Yŏngŭijŏng was also referred to as Yŏngsang (영상; 領相; lit. leading minister of state), Sangsang (상상; 上相; lit. upper minister of state), Sugyu (수규; 首揆; lit. head premier) or Wŏnbo (원보; 元輔; lit. primary assistant). Although the title of Yŏngŭijŏng was legally defined as the highest post in charge of all state affairs, its practical roles and powers shifted drastically throughout history as the roles of the State Council were not clearly defined in the Kyŏngguk taejŏn. During the early years of Joseon, the Yŏngŭijŏng saw limited roles in government as the Six Ministries reported directly to the king. Source: Wikipedia (en)