2025 marks 50 years of the Biological Weapons Convention. Back in 1975, the treaty entered into force, and by banning biological weapons worldwide, it became the first global treaty to prohibit a particular weapon of war. The Biological Weapons Convention is widely adopted — 189 States Parties have pledged to never develop, produce, stockpile, or use biological weapons. And thankfully, these weapons have not featured much in modern conflict. But over the last 50 years, profound advances in the life sciences and bio research have emerged which, according to my guest today, pose a distinct challenge to this treaty.

Jaime Yassif is the Vice President for Global Biological Policy and Programs at the Nuclear Threat Initiative, a nonprofit global security organization focused on reducing nuclear, biological, and emerging technology threats. We kick off by discussing the history of this treaty, including why the time was right 50 years ago for it to come together. We spend most of our conversation, though, exploring the ways in which this treaty might be strengthened to adapt to a changing landscape of potential biological weapons risks today.

This episode is produced in partnership with Lex International Fund, a philanthropic initiative dedicated to strengthening international law to solve global challenges. It's part of our ongoing series highlighting the real-world impact of treaties on state behavior, called "When Treaties Work."