Since 1994 Garretón has been full professor at the Department of Sociology, School of Social Sciences, at the University of Chile.
Garretón has served as visiting professor at European, North, and South American universities, and as Director and Dean of numerous academic institutions.
He was awarded the Guggenheim Fellowship in 1983, and chosen as the Simón Bolívar Professor of Latin-American Studies at the University of Cambridge, UK, for 2012-13.
He has also served on the board of several academic journals and has been a jury member for the award of research scholarships and fellowships.
Garretón was an executive of the Socialist Bloc between 1983 and 1985, was elected to the Socialist Party's Central Committee from 1985 to 1995, was a member of the Technical Committee for the Concertación de Partidos por el NO, and of the Concertación de Partidos por la Democracia for the plebiscite of 1988.