Becoming a Member State

OPCW's flag.

According to the Convention

Paragraph 2 of Article VIII of the Convention provides that "[a]ll States Parties to this Convention shall be members of the Organization".

Becoming a Member State

A state becomes State Party, and thereby a member of the Organisation, by one of three means - ratification, accession or succession. Instruments of ratification or accession must be deposited with the designated Depositary of the Convention, who is the Secretary-General of the United Nations (Article XXIII). The treaty enters into force on the 30th day following the date on which their instrument of ratification or accession was deposited (Article XXI).


Unlimited Duration

Given that the Convention is of unlimited duration (Article XVI), membership in the Organisation is also of unlimited duration; subject, of course, to the possibility of withdrawal.


A State Party shall not have a vote in the Organisation if it is in the arrears in the payment of its financial contribution, in an amount that equals of exceeds the amount of contribution due from it for the preceding two full years. The Conference "may, nevertheless, permit such a member to vote if it is satisfied that the failure to pay is due to conditions beyond the control of the member" (Article VIII).

Current Membership

The Organisation's current membership includes all Permanent Members of the United Nations Security Council, all countries with sizable chemical industry and countries from all regions of the world. Nonetheless, further enhancement of universality of membership remains a major aim of the Organisation.

Did You Know?

The entry into force on the CWC, 29 April 1997, simultaneously brought into being the OPCW. At that date:

  • 87 states had signed and ratified the Convention
  • 78 states had signed but not yet deposited their instruments of ratification