Ad hoc arbitration: A form of arbitration where the parties and the arbitrators independently determine the procedure, without the involvement of an arbitral institution.

Adjudicator: This broadly means a ‘decider’; it can be used to describe both judges and arbitrators, although sometimes it can mean either. However, it may also have the more specific meaning ascribed to it under adjudication, a distinct type of dispute resolution, whereby an adjudicator decides on a dispute. It is therefore important to understand the context in which it is used.

Arbitration agreement: An agreement, or more generally one of several clauses found in a longer commercial agreement, setting out that the parties agree to arbitration and usually setting out the rules and procedure. Arbitration agreements are separate from the remainder of the underlying agreement, meaning that if the underlying agreement is invalid, the arbitration agreement usually remains valid.

Arbitrator: The person(s) deciding the dispute between the parties.

Award: A decision on the merits of the dispute (generally on quantum and liability).

Bifurcation: The process of dividing proceedings up into separate parts. Usually, this will occur where a question arises which needs to be answered affirmatively for the dispute to proceed. A common example is whether a tribunal has jurisdiction to decide the dispute. If it does not, then it can also not decide the dispute on the merits.

Bilateral investment treaty: A treaty between two States on the protection of investments made by natural or legal persons from one country into the territory of the other.

Competence-competence: The principle that arbitrators have jurisdiction to decide on their own jurisdiction.

Consolidation: When two or more proceedings are combined, usually because they turn on similar or identical facts and involve similar or identical parties.

Counsel: Either party’s lawyers. Not to be confused with the UK term ‘counsel’, which frequently means barrister.

Damages: The money awarded to the successful party to compensate it for the injuries caused by the unsuccessful party.

Decision: Technically any type of decision by the tribunal that is not an order, thus including either final or interim awards.

Double-hatting: Describes arbitrators simultaneously acting as counsel and/or expert witnesses, especially during ISDS proceedings.

Due process paranoia: A reluctance by arbitrators to take certain steps out of fear of the award being challenged by a party based on allegations that it was, inter alia, not properly heard.

Enforcement: Once an award is rendered, it still needs to be ‘enforced’ against the debtor in a jurisdiction where it has assets, often corresponding to its jurisdiction of incorporation. This process is known as ‘enforcement’. Many countries are bound to enforce arbitral awards rendered abroad - see ‘New York Convention’ for further information.

Expert witness: An expert who provides evidence in relation to matters within their expertise. Frequently, expert witnesses will provide evidence on matters of either law or quantum.

Factual witness: A witness who provides evidence as to matters of fact, i.e., their personal experience in relation to a dispute.

Interim measures: Any measure awarded prior to the final award, that is to say, a temporary measure that is not decisive of the merits of the case. Common examples include freezing orders (preventing the disposal of assets), injunctions (prohibiting a party from taking certain actions), and security for costs (paying a deposit for the cost of proceedings).

Institutions: Also known as arbitral institutions, these centres provide a set of rules which parties can adopt to govern their arbitration. They frequently also administer arbitrations.

Investment Arbitration: see ISDS.

Investor-State Arbitration: see ISDS

ISDS: A system allowing investors from one country to bring arbitral proceedings against a country in which they have invested.

Jurisdiction: (1) Countries or states are often referred to as ‘jurisdictions’ - referring to the territory in which that country has legal ‘jurisdiction’; (2) Tribunals are often said to have (or not have) jurisdiction over a dispute. This essentially means that the dispute falls (or does not fall) within their remit of power.

Merits: Refers to what the actual dispute is about, i.e., the substance of the case. Broadly to be distinguished from the procedure or other relevant issues unconnected to the merits.

Model Law: UNCITRAL’s model arbitration law, produced with the aim of harmonising national arbitration laws. Many countries have adopted the Model Law, either entirely or in part: a list can be found here.

Moot court: A practice whereby students take part in simulated court or arbitration proceedings, usually involving the drafting of memorials or memoranda and making oral arguments. The most famous one in arbitration is the Vis moot (commercial arbitration), with the Jessup moot (international law) also being popular.

Multilateral Investment Treaty: An international investment agreement made between several countries and containing provisions to protect investments made by individuals and companies in each other's territories. See, for example, the Energy Charter Treaty or the North American Free Trade Agreement.

NAFTA: The North American Free Trade Agreement was a free trade agreement between the U.S., Canada, and Mexico that went into effect in 1993 and was replaced by USMCA in 2020 (see below).

New York Convention: Also known as the Convention on the Recognition and Enforcement of Foreign Arbitral Awards of 1958, the New York Convention provides a regime for the enforcement and recognition of arbitral awards within contracting states. Its widespread adoption is one of the main reasons international arbitration is so popular today.

Quantum: The amount of damages.

President / presiding arbitrator / chair: In a tribunal of more than one arbitrator, one arbitrator will need to be the president. This involves taking more of a leading role throughout the proceedings and also during any hearing. This is useful for the parties as it establishes a main point of contact, and is useful for the arbitrators as it effectively organises who will lead the proceedings. Whilst all arbitrators may be appointed by an institution, it will often be each party who appoint the co-arbitrators and the co-arbitrators who then together appoint the presiding arbitrator. Therefore, the presiding arbitrator may appear to be more ‘neutral’, although in theory, they are all impartial.

Procedural order: A procedural order is a document issued by the arbitrator(s) (although often drafted by the parties) laying down the rules for the arbitration. It will often include the rules for submitting documents, a timetable for the pleadings, and a schedule for the hearing, if any. Additional procedural orders will often be issued as the proceedings develop.

Request for arbitration: The initial claim filed by the claimant that starts the arbitral proceedings. It will usually be relatively short and only set out the most important facts.

Seat: The ‘legal home’ of the arbitration. It determines the law applicable to the procedure of the arbitration as well as the nationality of the award, i.e., what jurisdiction the award will be deemed to have been rendered in. The ‘seat’ is not necessarily the same as the venue: the hearings may be held elsewhere, or, as is increasingly common, virtually.

Separability: The doctrine of separability means that the arbitration agreement will survive the invalidity of the underlying agreement. Despite the name, it is usually not a separate agreement but rather a clause within a commercial contract.

Set aside proceedings: An action aimed at setting aside an award. Modern arbitration laws permit only a limited review of awards by local courts in set aside actions, and do not permit any review of awards’ merits. Awards set aside in their country of origin cannot be enforced in that country and may lose the benefit of enforcement under the New York Convention. However, some countries (such as France) allow an award set aside in its country of origin to be enforced in their territory if the conditions for doing so are fulfilled.

Submission agreement: A submission agreement is an agreement to arbitrate that is concluded after a dispute has arisen.

Substantive law: Usually describes the law applicable to the merits of a dispute, i.e., the law that will determine who wins the dispute on its facts. It may be different from the procedural law applicable to the dispute.

Terms of reference: A framework for the entire arbitration, setting out important factual details in relation to the dispute. It is very common in ICC proceedings but is also used in other types of institutional arbitration.

Third-party funding: Companies who pay the (partial) costs of proceedings and take a cut of the award if the party they are supporting is successful.

Tribunal: The collective name for the arbitrators who decide the dispute.

Tribunal secretary: The tribunal secretary is an aide of sorts to the tribunal. Despite the nomenclature, the role should not be understated. Often a senior associate from the law firm or chambers of one of the arbitrators, tribunal secretaries can play an important role, even drafting the award.

Umpire: A individual who resolves disputes between arbitrators where they cannot come to an agreement. Rare in practice, but occasionally used where there is an equal number of arbitrators, and possibly also where three or more arbitrators have a three or more-way split of opinion.

USMCA: The United States–Mexico–Canada Agreement is a free trade agreement between Canada, Mexico, and the United States. It is sometimes referred to as NAFTA 2.0 as it retains many of NAFTA’s provisions, with the most important updates being in the areas of intellectual property and digital trade.

Witness: See expert witness and factual witness.