Thomas Hajnoczi is a retired Austrian career diplomat who served as Director for Disarmament, Arms Control and Non-Proliferation and as Security Policy Director in the Foreign Ministry. Abroad he led the Austrian Permanent Mission to the UN (including the Conference on Disarmament) in Geneva and earlier the one to the Council of Europe. Before he had been Ambassador to Norway and Deputy Permanent Representative to the UN in New York.
He developed a particular interest in human security. He led the Austrian delegations to the negotiations resulting in the Treaty on the Prohibition of Nuclear Weapons and earlier those that brought about the Anti-Personnel Mine Ban Convention, of which he was the President in 2017. From 2020 to 2021 he was the Chair of the Missile Technology Control Regime.
In his retirement he advises the NGO Mayors for Peace and sits on the board of think tanks such as BASIC.