Sydney Dawson Bailey (1 or 2 September 1916 – 26 November 1995) was an English author, pacifist, and expert on international affairs.

He formally became a member of the Quakers while in China,[1][2][4][5] and, upon returning to England, he married Jennie Elena Brenda Friedrich (1923-2021) on 26 April 1945.

[2] Bailey taught himself political science[4] and began to research parliamentary systems around the British Commonwealth, though his primary focus soon shifted to be on the United Nations Security Council and disarmament.

Bailey was also involved in the establishment of the International Institute for Strategic Studies and several other similar groups, including a lectureship at King's College London on ethical problems with war and the Council on Christian Approaches to Defence and Disarmament (CCAD).

[7] From 1952 to 1976 Bailey organized several 10-day conferences, where diplomats from nations around the world met, notably including groups that "were not on talking terms" like the Arabs and Israelis.

[4][7] Michael Quinlan considered Bailey "one of the most significant of" the moral critics of nuclear deterrence, because he understood "strategic realities of the Cold War".