An arbitral tribunal or arbitration tribunal, also arbitration commission, arbitration committee or arbitration council is a panel of unbiased adjudicators which is convened and sits to resolve a dispute by way of arbitration. The tribunal may consist of a sole arbitrator, or there may be two or more arbitrators, which might include a chairperson or an umpire. Members selected to serve on an arbitration panel are typically professionals with expertise in both law and in friendly dispute resolution (mediation). Some scholars have suggested that the ideal composition of an arbitration commission should include at least also one professional in the field of the disputed situation, in cases that involve questions of asset or damages valuation for instance an economist.

The parties to agree on arbitration are usually free to determine the number and composition of the arbitral tribunal. Many jurisdictions have laws with general rulings in arbitration, they differ as to how many arbitrators should constitute the tribunal if there is no agreement. In some legal systems, an arbitration clause which provides for an even number of arbitrators is understood to imply that the appointed arbitrators will select an additional arbitrator as a chairperson, to avoid deadlock arising.

Arbitral tribunals are usually constituted (appointed) in two types of proceedings:

• ad hoc arbitration proceedings are those in which the arbitrators are appointed by the parties without a supervising institution, relying instead on the rules that have been agreed upon by the parties and/or procedural law and courts of the place of arbitration to resolve any differences over the appointment, replacement, or authority of any or all of the arbitrators; and
• institutional arbitration proceedings are those in which the arbitrators are appointed under the supervision of professional bodies providing arbitration services, such as the American Arbitration Association (which conducts international proceedings through its New York-based division, the ICDR), the Australian Fair Work Commission, the LCIA in London or the ICC in Paris. Depending on their establishing statutes or treaties, these kind of institutions can be capable of supervising the appointment of arbitration commissions in one country or on an international scale. This type of arbitration avoids the need for parties to involve local courts and procedures in the event of disagreement over the appointment, replacement, or authority of any or all of the arbitrators.

Permanent arbitration committees tend to have their own rules and procedures, and tend to be more formal. They also tend to be more expensive, and, for procedural reasons, slower.