Secretary-General of the United Nations the appointee's national origin and to gender equality, although no woman has yet served as Secretary-General. The length of the term is discretionary, but all Secretaries-General since 1971 have been appointed to five-year terms. Every Secretary-General since 1961 has been re-selected for a second term, with the exception of Boutros Boutros-Ghali, who was vetoed by the United States in the 1996 selection. There is a term limit of two full terms, established when China cast a record 16 vetoes against Kurt Waldheim's third term in the 1981 selection. No Secretary-General since 1981 has attempted to secure a third term. The
2016 United Nations Secretary-General selection As a result, the selection is subject to the veto of any of the five permanent members of the Security Council. The Charter's minimal language has since been supplemented by other procedural rules and accepted practices. Secretary-General Ban Ki-moon would be completing his second term on 31 December 2016, after which he would step down due to the informal two-term limit. Under the principle of regional rotation, candidates from Asia were ineligible to succeed Ban. The Eastern European Group was favored in the 2016 selection, as it was the only one of the United Nations Regional Groups never to have