The landscape of arbitrators in Spain

  • 31 August 2023 31 August 2023
  • Geopolitical risk

This is the first article in Clyde & Co’s latest international arbitration series covering the topic of the landscape of arbitrators across various international jurisdictions. In this piece, associate Marta Maciá from our Madrid office provides the legal perspective from Spain.


Arbitrators play a crucial role in the arbitration process, serving as impartial decision-makers who apply their expertise to resolve disputes. Their qualifications, backgrounds, and approach to arbitration significantly impact the outcome and credibility of the proceedings.

Spain boasts several prominent arbitration institutions that play a crucial role in facilitating efficient and impartial dispute resolution. In this article, we will delve into the landscape of arbitrators in Spain and explore the appointment rules and criteria followed by the key Spanish arbitration institutions. 

Mandatory rules on arbitrators’ appointment and disclosure obligations

The Spanish Arbitration Act No. 60/2003 (the "Spanish Arbitration Act") is inspired by the UNCITRAL Model Law and substantially adopts the disclosure requirements under the UNCITRAL Model Law.

General limitations

The requirements for selecting arbitrators under the Spanish Arbitration Act have few limitations. The limitations are as follows: 

  1. Natural persons who are in full exercise of their civil rights may be arbitrators, provided that they are not prevented from doing so by the law to which they may be subject in the exercise of their profession (Article 13 of the Spanish Arbitration Act). This is also the requirement for active judges and magistrates, members of the Public Prosecution Office, or practicing State Attorneys; 
  2. The nationality of a person shall not preclude him or her from acting as an arbitrator unless otherwise agreed by the parties (Article 13 of the Spanish Arbitration Act);
  3. Where the arbitration is to be decided by a single arbitrator, such a person will be required to be a jurist, unless parties agree otherwise or in matters subject to arbitration in equity (Article 15 of the Spanish Arbitration Act);
  4. When the arbitration is to be decided by three or more arbitrators, at least one of them shall be required to be a jurist (Article 15.1 of the Spanish Arbitration Act); and
  5. If a person has acted as mediator in a dispute, that person cannot be appointed as an arbitrator in the same dispute unless otherwise agreed by the parties (Article 17.4 of the Spanish Arbitration Act). 

Disclosure obligations

When a person is approached in connection with their possible appointment as an arbitrator, they must disclose “any circumstances likely to give rise to justifiable doubts as to his/her impartiality or independence”. An arbitrator, from the time of appointment and throughout the arbitral proceedings, must disclose any such circumstances to the parties (Article 17.1 of the Spanish Arbitration Act). 

There is no definition in the Spanish Arbitration Act of the “circumstances” that would give rise to justifiable doubts of an arbitrator’s impartiality or independence. However, Spanish arbitration practitioners and courts often use the 2014 IBA Guidelines on Conflicts of Interest and key case law as a guide.¹

Qualification and Backgrounds of Arbitrators in Spain. Encouraging diversity

Arbitrators in Spain possess a diverse range of qualifications and backgrounds, contributing to the richness and expertise of the arbitration community. Typically, arbitrators have extensive experience in law, often specializing in dispute resolution, commercial law, international law, or specific industry sectors. Many arbitrators hold advanced degrees, such as Master of Laws (LL.M.) or Doctor of Juridical Science (S.J.D.) and have completed specialized arbitration training programs. When selecting arbitrators, parties often consider factors such as the arbitrator's experience, reputation, expertise in the subject matter of the dispute, and language skills. Arbitrators in Spain often have a blend of professional experiences, including legal practice in law firms, corporate counsel roles, or academia.

The landscape of arbitrators in Spain is also international, comprising both Spanish nationals and foreign professionals. Foreign professionals are frequently appointed, particularly in cases involving cross-border disputes or parties from different jurisdictions. In these arbitrations, the presence of a foreign arbitrator can add an additional element of expertise in international matters.

The presence of women in arbitration practice has increased significantly in recent decades within Spain. However, it has been noted that parties are still choosing male arbitrators over female arbitrators and as a result, when the parties appoint the arbitrator there is less representation of women as arbitrators. To challenge this issue, Spanish arbitral institutions, authorities, associations and, in general, the Spanish arbitration community, have been using their platforms to encourage diversity in the selection of arbitrators. For example, Spanish arbitral institutions and law firms, including Clyde & Co, have signed up to the Equal Representation in Arbitration Pledge, which recommends actionable steps to increase the number of women being appointed as arbitrators in order to achieve a fair representation as soon practically possible. 

Appointment of Arbitrators in Key Arbitral Institutions in Spain

The Spanish Court of Arbitration within the Chamber of Commerce (Corte Española de Arbitraje), the Madrid Court of Arbitration (Corte de Arbitraje de Madrid, CAM), the Civil and Commercial Court of Arbitration (Corte Civil y Mercantil de Arbitraje, CIMA), the Centro Internacional de Arbitraje de Madrid (CIAM) and the Arbitration Court of Barcelona (Tribunal Arbitral de Barcelona, TAB) are prominent arbitration institutions that serve as pillars of Spain’s arbitration landscape. The following paragraphs expand on how these institutions contribute to the appointment of arbitrators in Spain.

Spanish Court of Arbitration 

The Spanish Court of Arbitration maintains an indicative list of approved arbitrators of diverse backgrounds and expertise. The indicative list is informative only and does not prevent professionals who are not included on the list from acting as arbitrators for the institution.

When acting as appointing authority, the Court follows a meticulous appointment process to ensure the selection of qualified arbitrators. Factors such as experience, reputation, and language skills are taken into consideration. Miguel Relaño and Luis Enrique Rodríguez, partners of our Madrid office, are members of the panel of arbitrators of the Spanish Court of Arbitration.

Madrid Court of Arbitration (Corte de Arbitraje de Madrid, “CAM”)

In contrast to the Spanish Arbitration Court, from July 2018 the Madrid Court of Arbitration decided to approve a new appointment system that did not offer an indicative list of approved arbitrators.  

The CAM maintains its own database of candidates, which may be supplemented by identifying other suitable profiles through alternative channels. Therefore, persons who are not included in the CAM’s database may be appointed as arbitrators in the proceedings administered by the CAM. 

The institution follows a transparent and merit-based approach, considering the qualifications, expertise, and specialization relevant to the dispute. The names of the arbitrators appointed by the CAM are published on the CAM’s website, together with the origin of the appointment (parties, co-arbitrators or the Court) and whether the case is still open or has been concluded. 

Civil and Commercial Court of Arbitration (“CIMA”)

CIMA is an arbitral institution with a long tradition in Spain. As of June 2023, it has a list of 134 arbitrators for regular proceedings which can be accessed through its website, with a personal profile of each of them and information about their expertise, academic background, arbitration experience and main publications. For arbitrations under 40,000 euros, there is also a list of 39 arbitrators accessible on CIMA’s website.

Articles 15 to 20 of the CIMA rules on the appointment of arbitrators only apply in the absence of an agreement of the parties. In any case, the general rule is that the arbitrators proposed or appointed must form part of CIMA’s list of arbitrators. 

Centro Internacional de Arbitraje de Madrid (“CIAM”)

The CIAM, which started operating in January 2020, is a very recent institution in Spain for international disputes. It is the outcome of the merger of the international activity of the CAM, the CIMA and the Spanish Court of Arbitration.

CIAM has its own set of rules on the appointment and confirmation of arbitrators (Annex 1 of CIAM Arbitration Rules). The general rule is that the parties are free to agree on all the arbitrators of the arbitral tribunal. In the absence of agreement, the CIAM will submit to the parties a list of arbitrators in a two-staged procedure: the proposal stage and the decision-making stage (Articles 1 to 3 of the Rules on Appointment of Arbitrators).

The proposal of candidates is prepared based on the candidates’ knowledge and experience, which must be appropriate to the complexity and relevance of the arbitration. Aspects such as nationality, language, need for specific technical expertise or availability will be taken into account, and additional factors, including the date of his or her last appointment, age, gender, or whether, if it is appropriate, to involve new professionals in the CIAM’s arbitration proceedings (Article 5 of the Rules on Appointment of Arbitrators).

Barcelona Arbitration Tribunal (“TAB” - Tribunal Arbitral de Barcelona)

The TAB is an arbitration institution based in Barcelona which mainly administers domestic disputes. The TAB follows rigorous appointment rules that consider the qualifications, experience, and reputation of arbitrators.

If arbitration is at law, only jurists with at least ten years of legal practice will be eligible candidates to be part of the list of accredited arbitrators of the institution, which as of June 2023 includes 207 arbitrators. 

Exceptionally, by agreement of the parties or for reasons arising from the uniqueness of a particular arbitration procedure, the TAB, by means of a reasoned agreement, may appoint an arbitrator from outside the TAB's list.

Spanish Arbitration Club (Club Español de Arbitraje)

The Spanish Arbitration Club is an arbitral body that brings together practitioners, scholars, and other professionals involved in arbitration. It provides a platform for networking, knowledge-sharing, and discussions on arbitration-related matters. The club organizes regular events, conferences, and seminars that facilitate the exchange of ideas and promote the highest standards of arbitration practice. Its collaboration with arbitration institutions, such as the Spanish Arbitration Court and the CAM, strengthens the ties between practitioners and institutions, fostering a cohesive and dynamic arbitration community.


Spain’s arbitration system has a robust framework for the appointment of arbitrators, prioritizing the right of appointment choice of the parties and ensuring the selection of qualified professionals with diverse backgrounds and expertise and high guarantees of independence and impartiality. Spanish arbitrators often possess advanced legal qualifications and practical experience, equipping them with the necessary knowledge and skills to manage complex disputes. The key arbitration institutions in Spain have established appointment rules that prioritize expertise, experience, and diversity. 

Thanks are due to Michelle Donovan, trainee lawyer of our Madrid office, for her research assistance.

This series will continue next week with the position from Egypt.

¹ High Court of Justice of Madrid judgment No. 28/2022, dated 12 July 2022 rejects that the independence and impartiality of an arbitrator is compromised because the arbitrator taught in the same law school as a counsel of one of the parties, with express mention that this situation was included in the Green List of the IBA Rules on Conflict of Interest as a situation where no appearance and no actual conflict of interest exists from and objective point of view and thus, the arbitrator had no duty to disclose situations falling within the Green List.


Additional authors:

Marta Maciá, Associate

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