He got the Chair of World and Spanish Economic History at the Economics Science College (Facultad de Ciencias Económicas), University of Santiago de Compostela in 1967, and the Chair of History and Economic Institutions at the Economics College (Facultad de Económicas), Universidad Complutense Madrid in 1968.

Member of the Royal Academy of History (Real Academia de la Historia) in 1978 and president since 1998. Founder of the Centro de Estudios de Política Exterior. Vice-president of the Fundación Duques de Soria. President of the Society for the XVIII Century Studies (Sociedad de Estudios del Siglo XVIII). Patron del Real Patronato of El Prado Museum and president for a few years. Vocal of the Government Board of the Fundación Príncipe de Asturias. Adviser of the Banco de España in 1983. Director of Moneda y Crédito. Honorary PhD from the universities of Oviedo and Alicante. Prizes: Nacional de Historia Prize (1995), Gran Cruz de Alfonso X el Sabio (1999), Gran Cruz de la Orden de Isabel la Católica (2002), Rey Juan Carlos in Economics Prize (2006), Jaume I in Economics Prize (2009). AEHE Prize for Outstanding Academic Achievement (2009).

He is one of the most outstanding eighteenth-century Spanish historians, specialized in Illustration, economic history and relationships between Spain and colonial Spanish America. Selected publications: Economía e ilustración en la España del siglo XVIII Ariel, 1969. Las crisis agrarias en la España moderna Taurus, 1970. El antiguo régimen: los Borbones Alianza, 1975. Historia económica y pensamiento social Alianza Editorial, 1983. La ley agraria Alianza, 1995. El siglo de las luces Alianza, 2001. Mesta, trashumancia y vida pastoril Madrid, 1994. Cultivos, pastoreo, diezmos y "Ley agraria" en España Real Academia de la Historia, 1998. Historia económica de España. Siglos XIX y XX Galaxia Gutenberg & Círculo de Lectores, 1999. Campomanes e II Centenario RAH, 2002.