Mr Annan filled a number of roles in his long diplomatic career at the UN from peacekeeping operations to managerial positions.
In 1990 he negotiated the release of hostages in Iraq following the invasion of Kuwait.
Five years later, he oversaw the transition of the UN Protection Force (UNPROFOR) to the multinational Implementation Force (IFOR), a UN peacekeeping organisation.
In this transfer of responsibility, operations in the former Yugoslavia were turned over to the North Atlantic Treaty Organization (NATO).
In recognition of his abilities, Mr Annan was appointed secretary-general, the top post of the UN, by the UN General Assembly in December 1996.
Mr Annan’s Nobel citation commended him for bringing new life to the peacekeeping organisation and highlighted the United Nations’s fight for civil rights.