Recurrence pattern: every year on November 27.

The International Day of Engagement in Science for Sustainable Development is observed worldwide every November 27. Established by UNESCO in April 2025, this day highlights the essential role of science in promoting human well-being, peace, and sustainable development. The resolution to create this observance was initiated by Ukraine and co-sponsored by 34 other countries. November 27 was chosen to honor the birthday of Borys Paton, a prominent Ukrainian scientist known for his contributions to electric welding and leadership of the National Academy of Sciences of Ukraine. The day promotes the exchange of expertise and innovation among scientists, educational institutions, and civil society, aiming to formalize scientific engagement as a foundation for sustainability. It encourages collaboration between science, education, policymakers, and the public to address complex social, economic, and environmental challenges effectively.