The official residence of the Secretary-General is a townhouse at 3 Sutton Place, Manhattan, in New York City, United States. The townhouse was built for Anne Morgan in 1921, and donated to the United Nations in 1972.

The Secretary-General of the United Nations (UNSG or just SG) is the head of the United Nations Secretariat, one of the six principal organs of the United Nations. The Secretary-General serves as the chief administrative officer of the United Nations. The role of the United Nations Secretariat, and of the Secretary-General in particular, is laid out by Chapter XV (Articles 97 to 101) of the United Nations Charter.

The Secretary-General was envisioned by U.S. President Franklin D. Roosevelt as a "world moderator", but the vague definition provided by the United Nations Charter left much room for interpretation. The Secretary-General is the "chief administrative officer" of the UN (Article 97) "in all meetings of the General Assembly, of the Security Council, of the Economic and Social Council and the Trusteeship Council, and shall perform other functions as are entrusted to him by these organs" (Article 98).

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