States-Parties and Signatories to The Chemical Weapons Convention

The Chemical Weapons Convention (CWC), which the United States signed on January 13, 1993, entered into force on April 29, 1997. The treaty bans the use, development, stockpiling, transfer, and acquisition of chemical weapons, and requires parties to destroy chemical weapons arsenals and production facilities. With entry into force of the convention, the Organization for the Proliferation of Chemical Weapons (OPCW) began formal operations in The Hague to implement the treaty's compliance and verification provisions.

As of April 19, 165 states have signed and 87 have ratified the convention. The table lists each state's date of signature and, where applicable, its date of ratification of the convention. States that have ratified the convention become members of the Conference of States Parties, the OPCW's main governing body. The Executive Council, the administrative organ of the OPCW, also oversees the Technical Secretariat, which is responsible for the inspection, verification, and data reporting provisions of the convention. The members of the Technical Secretariat and the Executive Council will be appointed by the Conference during its first session in May 1997.

Over 20 states possess or may be seeking an offensive chemical weapons capability, according to U.S. intelligence estimates. Although the countries possessing the largest chemical weapons stockpiles - Russia and the United States - have signed the CWC, several states of proliferation concern, namely Iraq, Libya, North Korea, and Syria, have not yet signed the treaty.