Participation in the Chemical Weapons Convention: How it Works

Paragraph 2 of Article VIII of the Convention provides that "[a]ll States Parties to this Convention shall be members of the Organization". A state becomes a State Party, and thereby a member of the Organisation, by one of two means — ratification or accession. 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 Convention entered into force on 29 April 1997, a period of 180 days after the date of the deposit of the 65th instrument of ratification (Article XXI, paragraph 1). The entry into force of the Convention simultaneously brought into being the OPCW. At the date of entry into force, 87 states had signed and ratified the Convention and were thus original members of the Organisation. At that time a further 78 states had signed the Convention, but had not yet deposited their instruments of ratification. These signatory states continue to be able to ratify the Convention after it has entered into force. States that did not sign the Convention prior to its entry into force may accede to it. For states whose instruments of ratification or accession are deposited with the Secretary General of the United Nations, as Depositary of the Convention, the treaty enters into force on the 30th day following the date on which their instrument of ratification or accession was deposited (Article XXI, paragraph 2).

The membership of the OPCW is comparable to that of other multilateral organisations/instruments of much longer standing in the field, such as the International Atomic Energy Agency and the Biological Weapons Convention. 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.

Given that, under Article XVI, paragraph 1, the Convention is of unlimited duration, membership in the Organisation is also of unlimited duration (subject, of course, to the possibility of withdrawal). Article VIII specifically guarantees that a State Party shall not be deprived of its membership in the Organisation. A State Party shall not, however, have a vote in the Organisation if it is in arrears in the payment of its financial contribution, in an amount that equals or 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, paragraph 8).