From 20 to 22 May 2025, the global metrology community came together in Paris and Versailles to mark 150 years since the signing of the Metre Convention—a milestone that celebrates both the legacy and future of international scientific cooperation.

The #BIPM150 programme was more than a commemoration, it served as a platform for scientific exchange, policy dialogue and strategic reflection.

Over three days of keynote addresses, panel discussions and thematic sessions, speakers explored how metrology supports progress across trade, technology, sustainability and space science.

This summary highlights the key messages and calls to action that emerged—centred on global collaboration, scientific innovation and sustainable development.

• Full programme and speaker details
• Watch sessions on the BIPM YouTube Channel

Key messages from the BIPM 150th anniversary events

Celebrating 150 years of the Metre Convention and its impact on science and innovation.

The discussions throughout the week stressed that the ongoing work of the BIPM in metrology gives hope for a better world and shows what can be achieved when people work together to advance science and society.

The celebrations included two keynote addresses:

Prof. William D. Phillips, Nobel Prize laureate 1997, National Institute of Standards and Technology (NIST), USA, on “The SI - a tool for all mankind”.

Prof. Ken Alder, Professor of History and author of “The Measure of All Things” Northwestern University, USA, on “From the Metric System to the Metre Convention”.

Highlighting the importance of accurate measurement for global trade, sustainable development and scientific collaboration

Many of the speakers mentioned the need to reinforce the message to policy makers and governments about the vital role of metrology to society, industry and innovation. This included detailed explanations of the economic impact of metrology.

• Precision in measurement is the cornerstone of global progress and innovation. (Ms Amal Kasry, Chief of Section for Basic Science, research, Innovation and Engineering, UNESCO - Closing session)
• Quality infrastructure (QI) is a driver of innovation in emerging economies and metrology is at its heart. [...] Metrology is (also) critical in adding value to raw materials and manufactured goods produced within Africa, particularly in the context of the African Continental Free Trade Area (AfCFTA). (Dr Henry Rotich, Director General, Kenya Bureau of Standards (KEBS) – Session 4).

Exploring emerging challenges and future directions in metrology and its role in addressing the United Nations Sustainable Development Goals (SDGs)

There was a common call during the events that global cooperation, equitable access and inclusive innovation must shape the next era of measurement. This aligns powerfully with the frameworks that guide the collective vision for metrology, particularly the International Decade of Sciences for Sustainable Development and the International Year of Quantum Science and Technology (IYQ).

• Meeting future challenges will require resilience, the ability to embrace complexity, to view challenges as opportunities and to learn from mistakes. (Dr Nathalie von Siemens, Advisory Board Member, Physikalisch-Technische Bundesanstalt (PTB), Germany – Session 4)
• The motivation and benefits must be explained for countries to participate in “big-science” projects such as CERN and the Square Kilometre Array (SKA). (Prof. Alessandro de Angelis, Scientific Attaché at the Permanent Delegation of Italy to the International Organisations in Paris – Session 2)
• The international time and frequency community needs to continue to build on the success of the reference time scale Universal Coordinated Time (UTC) [...] A new definition of the second is needed to account for data from new frequency standards [...] and a reference time scale is required for the Moon. (Dr Pascale Defraigne, Time and Frequency Service, Royal Observatory of Belgium – Session 4)
• The BIPM’s 150-year legacy reflects its strength in adapting to change, embracing digitalization and supporting open science. (Prof. Alessandro de Angelis – Session 2).

Fostering multilateral dialogue on capacity building and innovation in metrology

Cooperation has been a guiding principle of the BIPM over the last 150 years. To meet future challenges for global metrology it is essential to continue with this principle and to engage actively with young metrologists. The importance of education and understanding the needs of stakeholders are vital to meet future challenges in metrology.

• The importance of scientific diplomacy, local engagement and cross-sector collaboration must be reinforced. (Mr Shaofeng Hu, Director, Division of Science Policy and Basic Sciences, Natural Sciences Sector, UNESCO – Session 2)
• The value of regional metrology cooperation in building quality infrastructure that benefits individual nations. (Dr Sharonmae Smith-Walker, CEO, CARICOM Regional Organisation for Standards and Quality (CROSQ), Jamaica – Session 2)
• The value of 'open science' and the need to communicate the long-term societal value of international scientific cooperation. (Prof. Alessandro de Angelis – Session 2)
• Capacity building and knowledge transfer must be prioritized. (Prof. Mustafa Çetintaş, Director, TÜBITAK Ulusal Metroloji Enstitüsü (TÜBİTAK UME), Türkiye – Session 2)
• STEM education is vital to improve public understanding of metrology. (Dr Nathalie von Siemens – Session 4)
• “Observership” in the CIPM could bring significant benefits to emerging economies. (Dr Victoria Coleman, CIPM member and National Measurement Institute, Australia (NMIA) – Session 2; Dr Henry Rotich – Session 4).

Watch the sessions

All sessions from the BIPM150 celebrations are available to watch on-demand via the BIPM YouTube Channel.

Keynote Addresses

“The SI - a tool for all mankind”

“From the Metric System to the Metre Convention”

BIPM-UNESCO World Metrology Day Symposium

Opening session | Panel Discussion Navigating the Future of Metrology: Addressing the challenges of Scientific and Technical Multilateralism | Session 3: 150 years of international use of the Metric System | Panel Discussion Future challenges for global metrology |

150^th Anniversary Scientific Conference

Session 1: Metrology in the quantum era | Session 2: Metrology for climate science | Session 3: The FAIR digital revolution | Session 4: Poster preview session