Former Minister of Planning and Cooperation (1993-1996). During his term in office he was responsible for the preparation and implementation of the National Program for the Eradication of Poverty, the preparation and approval of regional development strategies in the 13 regions of Chile, and the consolidation of the Chilean government's "south-south" international cooperation programs.

Former Chilean Ambassador to Argentina and Mexico. Currently he is professor and researcher at the Center for Economic Research and Teaching (CIDE) in Mexico. President of the Chilean Students' Federation (1963-1964). Three times Congressional Deputy for Santiago between 1965 and 1973. In 1968 he was honored by the Circle of Political Journalists of Chile as the Best Deputy and in 1969 as the Best Documented Parliamentarian of the Chilean National Congress.

He lived in Mexico as a political exile from 1974 to 1985. In 1988 he joined the board of the National Command in favor of the "No" option on the occasion of the plebiscite held that year and which led to Chile's return to democracy. He was one of the founders that same year of the Alliance of Political Parties for Democracy, a political coalition thathas directed the destiny of the country since 1990. That same year he was elected Vice President and in 1992 Secretary General of the Socialist Party.

He is a former Director of the United States Studies Institute at the Center for Economic Research and Teaching (CIDE), Mexico. Former Professor at the National Autonomous University of Mexico (UNAM), and at the Catholic University of Río de Janeiro, as well as at FLACSO in Mexico and Buenos Aires. He has published fourteen books and over a hundred articles on international policy and Chile's current situation.