Verification today, tomorrow, together: Highlights from SnT2025

The eighth edition of the Science and Technology Conference (SnT2025) concluded on 12 September 2025, drawing more than 2,000 participants to Vienna and online. Scientists, technical and policy experts, academics, journalists and civil society representatives gathered to share knowledge and strengthen cooperation in support of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). 

Held under the theme Verification Today, Tomorrow, Together, the week-long programme moved through five daily focuses: Online Day, High-Level Day, Quantum Day, Together Day and Future Day. This structure gave space for distinct perspectives while building a coherent narrative across the week. 

For the first time, High-Level Day offered interpretation in international sign language, alongside the six official languages of the CTBTO Preparatory Commission: Arabic, Chinese, English, French, Russian and Spanish. 

Beginning with an online opening and continuing at Vienna’s historic Hofburg Conference Centre, the agenda combined high-level addresses, presentations, panel discussions and oral sessions. With both in-person and virtual participation, the conference amplified diverse voices while showcasing scientific and technological advances that underpin the CTBT and its verification regime. 

High-Level Day also featured statements of support from United Nations High Representative for Disarmament Affairs Izumi Nakamitsu, Francisco Rondinelli Junior, Director General of Brazil’s National Nuclear Energy Commission (CNEN), and Pennapa Kanchan, Acting Secretary-General of Thailand’s Office of Atoms for Peace. 

A panel, 90 to 100: IMS Completion Through Collaboration, addressed the path towards finalising the International Monitoring System (IMS), which is 92 percent complete. Representatives of Malaysia, Mongolia, Namibia and South Africa shared national perspectives on sustaining the network, improving data access and broadening civil and scientific applications. 

Another session, Today’s Minds, Tomorrow’s Innovators, examined how equity, gender balance and generational diversity strengthen verification efforts. The European Union reaffirmed its long-standing support for the CTBT, highlighting ongoing Joint Actions and Council Decisions that provide political and financial backing. 

SnT2025 placed strong emphasis on generational, gender and geographic diversity. Youth voices were woven throughout the programme, particularly through two standout initiatives. 

The first was led by the Organization’s CTBTO Youth Group (CYG). Six content creators, winners of the Be the Voice of SnT2025 contest, produced multilingual social media content that amplified the Organization’s message worldwide. CYG also presented a Roadmap for the Group’s future to the CTBTO head and joined a roundtable with global youth networks, building partnerships and setting priorities for years ahead. 

The second featured 12 mentees from the flagship Mentoring Programme, representing all six geographical regions. Having completed the 2025 cycle the week before the conference, they travelled to Vienna for SnT2025. Their agenda included sessions delivered by former mentees, meetings with States Signatory representatives and a visit to the IDC Operations Centre.  

SnT2025 featured a wide range of technical sessions looking at how the CTBT verification system is evolving and adapting to new challenges. 

At the International Data Centre (IDC), discussions highlighted both current operations and future directions. One session examined the software and hardware provided to National Data Centres (NDCs), which help States Signatories analyse CTBT data more effectively. 

On-Site Inspection (OSI) was also a key focus, with experts discussing how recent field exercises and emerging technologies are enhancing inspection techniques and improving readiness ahead of the Treaty’s entry into force.

Finally, the role of artificial intelligence was explored in the session AI Applied to Science. Speakers outlined how AI can support data analysis and detection across the CTBT system, while also weighing the opportunities and challenges of bringing these tools into verification work. 

SnT2025 offered interactive exhibits across the Hofburg Conference Centre. Participants tested virtual-reality experiences simulating on-site inspections, explored IMS and IDC applications, and took part in an NDC escape room. Divisions across the CTBTO also showcased their work, from Public Information to Human Resources. 

All sessions were streamed live, including via UN Web TV and a dedicated SnT2025 app. Online engagement reached 3,425 unique viewers across 118 countries, with more than 4,900 total log-ins during the week. While some users may have connected through multiple devices, these figures mark a significant increase compared with SnT2023. 

As in previous editions, the CTBTO supported under-resourced journalists to attend, with this initiative partly funded by the European Union. Selected participants from Brazil, Egypt, India, Kazakhstan and Mexico took part in tailored briefings on the CTBT’s role in non-proliferation and disarmament, and produced some 20 pieces of coverage across print, broadcast, digital and podcast media. 

Awards were presented at the closing ceremony in categories including Early Career Scientist, Best Oral Presentation, Best E-Poster (scientific and technology), Greatest Advancement in Treaty Monitoring, and the EU Star Award. 

Presenters included the Directors of CTBTO’s Divisions, Ambassador Carl Hallergård, Permanent Representative of the European Union to the International Organizations in Vienna, and Robert C. Kemerait, the oldest participant at 91 years old and a retired colleague from a United States National Data Centre. 

The ceremony also featured a video message from Jane Goodall, who praised the CTBTO’s mission as aligned with her own efforts to safeguard the planet and work with future generations.