The United Nations Office at Vienna is generally less accessible than Geneva and New York. The largest institution is the International Atomic Energy Agency, which accounts for half of the office space. When we entered the door, the national flags of each country were displayed in the wind, but then the staff began to take down the national flags one after another, saying that they learned that the head of the IAEA had died today, so it was customary for the national flags of the Organization and the United Nations to be taken down at half-mast.