On July 1, 1968, the Treaty on the Nonproliferation of Nuclear Weapons was opened for signature in three Depository state capitals: Washington, London, and Moscow. This year we mark the NPT’s 50th anniversary. The United States celebrates this important milestone and applauds the immeasurable contribution this landmark treaty has made to international security. The NPT has provided the essential foundation for international efforts to stem the looming threat – then and now – that nuclear weapons would spread across the planet.

The maintenance of a strong nonproliferation regime grounded in the NPT helped create a secure and stable security environment conducive to progress in nuclear disarmament. The NPT facilitates cooperation on peaceful uses of nuclear energy that diagnose and fight diseases, develop new crops, manage scarce water resources, and broadly apply nuclear science and technology that meet UN Sustainable Development Goals.

In honor of the 50th anniversary of the Treaty on the Nonproliferation of Nuclear Weapons, and to mark the occasion, we have begun an historical access project to make available documents relating to NPT history. The project includes newly declassified scenario documents and background memos leading up to the NPT’s signing in Washington as well as the Arms Control and Disarmament Agency’s in-house history of the Eighteen-Nation Disarmament Committee. We hope to continue this effort leading up to the 2020 anniversary.

U.S. Department of State

Welcome to the new State.gov

Our new design makes it easier to find and learn about the State Department’s programs and services—from passports and visas to learning how U.S. diplomacy benefits the American people.