Xavier Trias was born in Barcelona in 1970. He graduated in Medicine and Surgery from the University of Barcelona and specialised in paediatrics. Between 1971 and 1973, he completed his postgraduate studies in Genoa, Italy, and Bern, Switzerland. In Bern, Dr. Trias researched metabolic diseases, their diagnosis and treatment for a year and a half.

He worked as a paediatrician in the Vall d’Hebron Children’s Hospital between 1974 and 1981. Between 1979 and 1981, he was a national hospitals spokesperson at the General Council of Official Medical Colleges of Spain, and a hospitals spokesperson at the Board of the Official Medical College of Barcelona.

In 1981, he joined the Health and Social Services Ministry of the Government of Catalonia as the head of Hospital Services. In September 1983, he became the general manager of Health Care Planning.

In July 1984, he was appointed General Manager of the Catalan Health Institute (ICS, in Catalan). He held this office until he was appointed Minister of Health of the Catalan Government in July 1988.

In January 1996, he was appointed Minister to the Presidency and Spokesperson of the Government of Catalonia.

He was the head of the Convergence and Union (CiU, in Catalan) candidacy for the Spanish Parliament in the elections of March 2000. Upon becoming an MP in the Spanish Parliament, he was appointed president and speaker of his parliamentary group, and president of the Science and Technology Commission of the Spanish Parliament.

In 2003, Xavier Trias was elected Councillor of the Barcelona City Council as a representative of Convergence and Union. Between July 2011 and July 2015, he was the elected Mayor of Barcelona and president of the Barcelona Metropolitan Area.