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Diego Luis Alonso Massa

Foreign Legal Consultant

Diego Alonso is an international arbitration lawyer and legal researcher with two decades of experience advising States, State-owned entities, and private clients in high-stakes investment and commercial arbitrations under ICSID, UNCITRAL, ICC, and ICSID (AF) rules. With a solid foundation in both civil and common law systems, extensive work at the national and international levels—including with UNCITRAL, the ILO, WIPO, and IMO—and strong language skills in more than seven languages, Diego brings a valuable combination of legal expertise and cross-cultural competence to complex transnational disputes.

Diego brings over three decades of legal experience at both the national and international levels to our team, including legal advisory and legal translation roles with specialized agencies of the United Nations system, as well as private practice experience in Latin America, including serving as Head of the LatAm Intellectual Property Department of a multinational company in Buenos Aires and São Paulo. His work frequently involves high-stakes international arbitration claims and the application of foreign law, often under ICSID, UNCITRAL, ICC, and ICSID (AF) rules.

He is the founder and lead editor of IarbNews, a multilingual platform focused on international investment arbitration. Diego has authored a number of articles published in journals, including TDM, Revista de Arbitraje Comercial y de Inversiones, and the Journal of International Arbitration. He has also translated and analysed a wide range of legal texts and decisions related to international law and arbitration across several languages.

*Licensed to practice law in Argentina. Practice is limited to international arbitration matters.

Practice Areas

Education

Ph.D., Université du Québec à Montréal, International Law
L.L.M., University of Geneva
University of Buenos Aires, law degree and a specialized degree in legal translation

Languages

English, Spanish, French, Italian, Portuguese, Catalan, German, Dutch, Swedish, Romanian

State Bar Licenses

Argentina

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