[2] He speaks seven languages: Spanish (mother tongue), English, French, German, Greek, Italian and Portuguese.
He started there as a trainee and later assistant of the then MEP Enrique Barón, who three years later included him in his Cabinet as adviser from 1989 to 1991 after being appointed President of the European Parliament.
[2] From 1997 to 2004 he was the Main Advisor of the European Parliament Secretary General Cabinet, Julian Priestley.
[7] In June 2018 he accepted the offering of the Foreign Minister, his former boss and former EU Parliament President Josep Borrell to replace Jorge Toledo Albiñana as Secretary of State for the European Union.
[8] In February 2020, the new foreign minister Arancha González Laya, appointed Juan González-Barba Pera to replace Aguiriano.