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Proliferation Security Initiative

The Proliferation Security Initiative (PSI) is a global effort that aims to stop trafficking of weapons of mass destruction, their delivery systems, and related materials to and from state and non-state actors of proliferation concern.


Proliferation Security Initiative

Launched by the President May 31, 2003, U.S. involvement in PSI stems from the U.S. National Strategy to Combat Weapons of Mass Destruction issued in December 2002.

In February 2004, U.S. Customs and Border Protection began its involvement when the PSI was expanded to include law enforcement cooperation. Today, more than 100 countries around the world have endorsed the PSI.

United Nations Security Council Resolution (UNSCR) 1540, adopted unanimously by the Security Council, calls on all states to take cooperative action to prevent trafficking in WMD.

PSI is an innovative and proactive approach to preventing proliferation that relies on voluntary actions by states, consistent with national legal authorities and relevant international law and frameworks, to fulfill the U.S. obligation to UNSCR 1540. PSI participants use existing authorities (national and international) to put an end to WMD-related trafficking and take steps to strengthen those authorities as necessary. Operationally, CBP can regularly take action to interdict WMD-related materials through its existing border search authorities.


PSI Exercise Pacific Protector

CBP Lab Experts participate in PSI Exercise Pacific Protector, designed to test international authorities and capabilities to interdict WMD materials.


CBP has been designated as a lead USG agency for law enforcement-related PSI issues, including coordination with other law enforcement agencies and the global law enforcement and Customs community. Law enforcement engagement provides the PSI with expertise in intelligence and information sharing, industry outreach, targeting and analysis, response and interdiction actions, and the methods to halt proliferation networks through criminal investigations, prosecutions and asset seizures.

Since 2004, CBP has maintained a leadership role among the global PSI law enforcement community, through active participation in PSI exercises, policy and operational experts meetings, industry outreach and capacity building around the world.

CBP PSI activities are designed to employ the full range of CBP enforcement programs, automation tools, technology, industry outreach, and highly trained law enforcement personnel in support of non-proliferation efforts. This includes helping other countries in their WMD interdiction efforts. The program builds upon current CBP non-proliferation efforts such as those designed to improve targeting and extend the border. For more information on the PSI, visit the U.S. Department of State's website.

Last modified: 
February 9, 2014