On June 6 and 7,2022, the China Arms Control and Disarmament Association (CACDA) and Federation of American Scientists (FAS) jointly held the virtual international seminar on the Comprehensive Nuclear-Test-Ban Treaty (CTBT). CACDA Secretary General Li Chijiang and FSA Senior Fellow Jennifer Mackby attended and delivered opening remarks. More than 40 officials, experts and scholars from Secretariat of the CTBTO Preparatory Commission, China, the U.S., Germany, Italy, Sweden, Japan,and other countries,attended the meeting. Participants had in-depth discussions on issues including promoting the universality of CTBT, the verification regime of CTBT, international monitoring systems and advances in on-site verification technology.