Executive Secretary Lassina Zerbo (centre) and the UN Disarmament Fellows

At the infrasound test-bed station at the Vienna International Centre

At the seismic test-bed station at the Vienna International Centre

Working on the group research assignment

Equipment check as part of the on-site inspection table-top exercise

Negotiations at the on-site inspection table-top exercise

Twenty-five UN Disarmament Fellows from countries in all five continents participated

UN Disarmament Fellows at the CTBTO

A group of 25 United Nations (UN) Disarmament Fellows - young diplomats from countries in all five continents - participated in a four-day study visit hosted by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO).


The Fellows are participating in three-month programme that aims to build the capacity of officials from UN Member States to enable them to participate more effectively in international disarmament deliberating and negotiating fora. The programme was launched in 1978 and is implemented by the UN Office for Disarmament (UNODA).

The Treaty that bans all nuclear explosions

The programme's CTBTO segment offers an in-depth look at the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and its verification regime, as well as the challenges of achieving the Treaty’s entry into force and universalization.

I think it was very, very stimulating. The experiences I’ve had here in the CTBT and in Vienna as a whole will help my career. Miriam Aba Arhin, Ghana

The annual study visit is a key element of the ongoing educational collaboration between the CTBTO and UNODA. Executive Secretary Lassina Zerbo welcomed the Fellows to the CTBTO with the message that:

You are the next generation of experts in arms control and non-proliferation…You will make a difference and this is what I am asking you to do.CTBTO Executive Secretary Lassina Zerbo

Zerbo also highlighted the destabilizing and damaging effects of nuclear testing throughout the Cold War and the urgency of and importance of securing the Treaty’s entry into force to prevent a backsliding to an era of unrestrained testing. He also emphasized the global significance of the CTBT and the role of all States in participating in the Treaty’s implementation. 

What we are ultimately trying to do is build peace, security and stability for all of us. This is not just an issue for the nuclear weapon States. This world is changing so fast. There are no big players. We are all big players. We are all interconnected [as are] the issues that we are dealing with.Executive Secretary Lassina Zerbo
CTBTO Executive Secretary Lassina Zerbo

The Fellows engaged with CTBTO experts on the political, legal and technical aspects of the Treaty, including the history of nuclear testing and nuclear weapons development, the CTBT’s role in international peace and security, as well as prospects for its entry into force and universalization. The Fellows also participated in group research assignments that required them to utilize knowledge gained throughout the programme to respond to critical questions about the Treaty.

The CTBT introductory course and its module were very informative. The demonstrations on the verification regime proves once and for all the value of the system for nuclear non-proliferation and disarmament.Munyaradzi Amon Benedict Tumbare, Zimbabwe
At the infrasound test-bed station

CTBTO scientists provided perspectives on the technical and scientific aspects of the Treaty, and the Fellows witnessed first-hand the works of the International Data Centre Operations Centre and test-bed monitoring stations on the grounds of the Vienna International Centre.

The program is well-designed, offers a good balance between theory and practice and is intellectually stimulating.Jorge Adalberto Gonzales-Mayagoitia, Mexico

The Fellows also engaged in a discussion on various national perspectives and positions on the Treaty with representatives of CTBTO Member States in which domestic and regional concerns regarding nuclear testing and the importance of the CTBT were expressed.

Hearing insights from Permanent Representatives to the CTBTO highlighted the domestic issues regarding Treaty ratification, which are often overlooked.Caroline Yvonne Steller, Germany
From left: Tamara Fitzgerald, U.S. mission to the UN Vienna and Zhang Shen, from China's mission to the UN Vienna
Equipment check as part of the on-site inspections table-top exercise

On the third day of the seminar, the Fellows conducted an on-site inspections (OSI) table top exercise. Playing the role of inspection team and inspected State party representatives, Fellows simulated some of the complex initial logistical planning procedures for an on-site inspection.

I really appreciated the practical part of the programme, especially the OSI simulation and the interactive sessions.Masa Grimm, Serbia