He graduated in law from the Universidad Complutense in Madrid in 1954.
He did his postgraduate studies between 1955 and 1957 at Chicago University.
He obtained a doctorate with special prize in 1959 with his thesis, “La familia española en transición".
In 1960 he obtained the sociology chair at the Faculty of Political Sciences in Madrid.
In 1962 he was professor of sociology at Barcelona University's Faculty of Political, Economic and Business Sciences.
In 1967 he was professor of sociology at the Universidad Complutense.
From 1977 to 1980 he was Dean of the School of Political Sciences and Sociology.
From 1971 to 1999 he was head of the Social Structure Department.
He has collaborated with the United Nations in different posts in matters relating to population studies.
He was the main promoter and founder of the Institute de Opinion Pública (today the CIS), becoming its Managing Director in 1963 and then its Director, from 1967 to 1971.
He became a tenured member of the Spanish Royal Academy of Moral and Political Sciences in 1980 and in 1985 was appointed Secretary.
He was appointed Chairman of the Spanish Institute in 2004.