Antonio Hierro is head of the Cuatrecasas litigation and arbitration division, which currently has over 220 lawyers, organised into 20 specialised teams. He previously served as a counsel for the state in the international jurisdiction for the Ministry of Foreign Affairs, where he also acted as legal adviser to the Spanish government on negotiating the Treaty of the European Union (the Maastricht Treaty). Mr Hierro acts regularly as an ad hoc arbitrator and arbitrator in different international courts, preferably in the International Court of Arbitration of the ICC. He has been particularly active in construction, energy, joint ventures and M&A arbitration cases.