ICSID has a simple organizational structure consisting of an Administrative Council and a Secretariat.

The Administrative Council is the governing body of ICSID. It is comprised of one representative of each of the ICSID Contracting States. The Administrative Council convenes annually in conjunction with the joint World Bank/International Monetary Fund annual meetings. All representatives have equal voting powers. The President of the World Bank is ex officio Chairman of the ICSID Administrative Council but has no vote.

Principal functions of the Administrative Council include the election of the Secretary-General and the Deputy Secretary-General, the adoption of regulations and rules for the institution and conduct of ICSID proceedings, the adoption of the ICSID budget, and the approval of the annual report on the operation of ICSID.

The Secretariat consists of a Secretary-General, a Deputy Secretary-General and staff. The Secretary-General is the legal representative of ICSID, the registrar of ICSID proceedings and the principal officer of the Centre. The Deputy Secretary-General is responsible for the day to day operation of the Secretariat and acts for the Secretary-General in the event of his/her absence or inability to exercise duties and during any vacancy in the office of Secretary-General.

Mr. Nassib G. Ziadé currently serves as Deputy Secretary-General. Upon the departure of Ana Palacio from the World Bank Group on April 15, 2008, he has also served as Acting Secretary-General.

Principal functions of the Secretariat include providing institutional support for the initiation and conduct of ICSID proceedings; assistance in the constitution of conciliation commissions, arbitral tribunals and ad hoc committees and supporting their operations; and administering the proceedings and finances of each case. The Secretariat also provides support to the Administrative Council and ensures the functioning of ICSID as an international institution and a center for publication of information and scholarship.

The Secretariat maintains the ICSID Panels of Conciliators and of Arbitrators to which each Contracting State may designate four persons and the Chairman of the Administrative Council may designate 10 persons. The ICSID Panels provide a source from which the parties to ICSID proceedings may select conciliators and arbitrators. Further, in the event the Chairman of the Administrative Council is called upon to appoint conciliators, arbitrators or ad hoc committee members in ICSID proceedings, his appointees must be drawn from the Panels.

The Secretariat's administrative costs are financed out of the World Bank's budget; the costs of ICSID proceedings are borne by the disputing parties.