Ambassador Tibor Tóth has been the Executive Secretary of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) since 2005. The CTBTO is the international organization tasked with promoting and monitoring compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which bans all nuclear explosions.
Ambassador Tóth has been actively involved in international disarmament and non-proliferation issues for over three decades. From 1990 to 1993 and from 2003 to 2005, he was the Ambassador and Permanent Representative of Hungary to the United Nations in Geneva. From 1997 to 2001 he served in the same capacity to the United Nations in Vienna. In these capacities he represented Hungary at the Conference on Disarmament, the International Atomic Energy Agency and its Board of Governors, as well as the CTBTO. He was also Ambassador and Permanent Representative to the Preparatory Commission of the Organization for the Prohibition of Chemical Weapons in the Hague, and from 1994 to 1996 served as the Deputy State Secretary of Defense responsible for international affairs.
From 1992 to 2004, he chaired the Biological Weapons Convention negotiations on an implementation and verification regime. In 1992 he negotiated the Chemical Weapons Convention provisions on the Executive Council and in 1990 he initiated the joint organization of the Open Skies Conference by Canada and Hungary (later depositaries of the 1992 Treaty on Open Skies, which established a programme of unarmed aerial surveillance flights over all NATO and Warsaw Pact countries).