ICSID does not conciliate or arbitrate disputes; it provides the institutional and procedural framework for independent conciliation commissions and arbitral tribunals constituted in each case to resolve the dispute.

ICSID has two sets of procedural rules that may govern the initiation and conduct of proceedings under its auspices. These are: (i) the ICSID Convention, Regulations and Rules; and (ii) the ICSID Additional Facility Rules.

ICSID Convention, Regulations and Rules

The ICSID Convention provides the basic procedural framework for conciliation and arbitration of investment disputes arising between member countries and investors that qualify as nationals of other member countries. This framework is supplemented by detailed Regulations and Rules adopted by the ICSID Administrative Council pursuant to the Convention.

A principal feature of conciliation and arbitration under the ICSID Convention is that they are based on a treaty establishing an autonomous and self-contained system for the institution, conduct and conclusion of such proceedings.

Arbitration and conciliation under the Convention are entirely voluntary, but once the parties have given their consent, neither may unilaterally withdraw it. A further distinctive feature is that an arbitral award rendered pursuant to the Convention may not be set aside by the courts of any Contracting State, and is only subject to the post-award remedies provided for in the Convention. The Convention also requires that all Contracting States, whether or not parties to the dispute, recognize and enforce ICSID Convention arbitral awards.

There are several essential jurisdictional conditions for access to arbitration or conciliation under the ICSID Convention:

• The dispute must be between an ICSID Contracting State and an individual or company that qualifies as a national of another ICSID Contracting State. (ICSID Contracting States may designate constituent subdivisions and agencies to become parties to ICSID proceedings).
• The dispute must qualify as a legal dispute arising directly out of an investment.
• The disputing parties must have consented in writing to the submission of their dispute to ICSID arbitration or conciliation.

Under the ICSID Convention, the Secretary-General is vested with the limited power to "screen" requests for institution of ICSID conciliation and arbitration proceedings, and to refuse registration, if on the basis of the information provided in request, the Secretary-General finds that the disputes is manifestly outside the jurisdiction of the Centre.

ICSID Additional Facility Rules

Besides providing facilities for conciliation and arbitration under the ICSID Convention, the Centre has since 1978 had a set of Additional Facility Rules authorizing the ICSID Secretariat to administer certain types of proceedings between States and foreign nationals which fall outside the scope of the Convention.

These include :

• Conciliation and arbitration proceedings for the settlement of disputes arising directly out of an investment where either the State party or the home State of the foreign national is not an ICSID Contracting State.
• Conciliation and arbitration proceedings between parties at least one of which is a Contracting State or a national of a Contracting State for the settlement of disputes that do not directly arise out of an investment.
• Fact-finding proceedings.

Other Dispute Settlement Activities of the Centre

Additional activities of ICSID in the field of the settlement of disputes have included the Secretary-General of ICSID accepting to act as the appointing authority of arbitrators in ad hoc (i.e., non-institutional) arbitration proceedings. This is most commonly done in the context of arrangements for arbitration under the Arbitration Rules of the United Nations Commission on International Trade Law (UNCITRAL), which are specially designed for ad hoc proceedings. At the request of the parties and the tribunal concerned, ICSID may also agree to provide administrative services for proceedings handled under the UNCITRAL Arbitration Rules. The services rendered by the Centre in such proceedings may range from limited assistance with the organization of hearings and fund-holding to full secretariat services in the administration of the case concerned.