Bachelor of Laws, Carnegie Institute Geneva. Postgraduate degree in public law, Carnegie Institute Geneva.
He was the Permanent Representative of Côte d"Ivoire to the United Nations from 1981 to 1990, and in January 1990 he was President of the United Nations Security Council. In 1990 he became Minister of Foreign Affairs, and while in that position he served as President of the 49th Session of the United Nations General Assembly from 1994 to 1995. In 1998 he gained the rank of Minister of State, while remaining Foreign Minister.
Along with other ministers, he was detained following the military coup of 24 December 1999, but he was released on 28 December.
He was replaced in the transitional government named on 4 January 2000. He took office as secretary-general in Addis Ababa, Ethiopia on 17 September 2001.
Essy served in that position until 9 July 2002, when the Organization of African Unity became the African Union and he was appointed as interim Chairman of the Commission of the African Union. Essy was initially a candidate for the post of Chairman of the Commission at the AU"s July 2003 summit in Maputo, but he withdrew prior to the vote, leaving Alpha Oumar Konaré, the former President of Mali, as the only candidate.
Essy remained interim Chairman of the Commission until he was succeeded by Konaré on 16 September 2003.
Married Lucie, 1971; children: Nicolas, Abdoulaye, Myriam, Mathy, Adama, Ismaël, Leila.