Described as a “dominant force in the international arbitration community” and “a skilled investigator, case strategist, and disciplined team leader,” Hioureas has been recognized in Chambers & Partners - Global and USA: Arbitration, Public International Law and Arbitrators, respectively (2020-23), as a “Most Highly Regarded Partner–The Americas” by Who’s Who Legal (2023) and “Attorney of the Year” by the Hellenic Lawyers Association (2022). Hioureas has acted for and advised States including Bangladesh, Chile, Croatia, Cyprus, Ghana, Greece, Guyana, Japan, Liechtenstein, Luxembourg, Mauritius, Montenegro, Qatar, Sierra Leone and Uzbekistan and various State-owned and private entities across jurisdictions and industries. Her experience includes:
- As counsel in international commercial arbitration (ICC, ICDR, AAA, SIAC, LCIA, UNCITRAL and Swiss Rules) and investment treaty disputes (ICSID, UNCITRAL) ranging from construction, hospitality, taxation, and shareholder matters to gas pricing/re-opener, energy supply, and solar power arbitrations under investment treaties and foreign investment laws, as well as joint venture, EPC, sale and purchase, power purchase, joint development, offtake, and long-term lease agreements, with amounts at stake from $120 million to over $10 billion.
- As Presiding, Sole, Emergency and Co-Arbitrator in disputes under UNCITRAL, ICC, ICDR, LCIA, and AAA Rules relating to construction, natural gas, renewables, hospitality, franchise, supply chain, pharmaceuticals, fashion, technology, civil rights, and cyber-security. She is also a CEDR-certified mediator.
- As counsel to States before the United Nations (Security Council and General Assembly) and before regional human rights tribunals and the International Court of Justice relating to decolonization, jus cogens, law of occupation, protection of the environment during armed conflict, sea level rise, and rendition.
- As counsel in claims before U.S. courts under the Alien Tort Statute and the Torture Victim Protection Act in cases alleging extrajudicial killing, torture, cruel treatment, arbitrary detention, and crimes against humanity; Foreign Sovereign Immunities Act in connection with embassies and consulates; and defense and enforcement of arbitral awards under the Federal Arbitration Act.
She is a U.S. member of the ICC Commission on Arbitration, delegate of Greece to the International Law Association’s Committee on International Law and Sea Level Rise, Term Member of the Council on Foreign Relations and Executive Council member of the American Society of International Law.