During the government of President
Eduardo Frei Montalva, Silva Cimma chaired the National Commission for Rationalization, working with subsecretaries
Adolfo Zaldívar, Juan Hamilton, and Patricio Rojas. Under his administration, measures such as the implementation of the single school day, the introduction of exempt presidential decrees to reduce administrative burden, and efforts to prevent political distribution of public offices were adopted. In 1961, he was a candidate for the Seventh Provincial Grouping of Ñuble, Concepción, and Arauco, replacing Humberto Enríquez Frodden. He served as a substitute justice of the
Supreme Court of Chile between 1968 and 1973. Concurrently, during the government of President
Salvador Allende, he was appointed President of the first Constitutional Court of Chile between 1971 and 1973. Following the military coup of 11 September 1973, he traveled to Spain for four months to teach a law course and later emigrated to Venezuela, where he served as a professor at the
Central University of Venezuela and as an advisor to the Comptroller General of the Republic of Venezuela. During the period of political clandestinity, he served as president of the
Radical Party of Chile from 1983 to 1990 and as a member of its National Executive Committee. In 1990, more than 300 assemblies were created and the Center for Research and Studies of Democratic Socialism (CIEDE) was founded, financed by the German Social Democratic Party. He served as a member and vice-president of the Bureau of the
Socialist International. From 1984, he served as president of the Democratic Socialist Federation of Chile. In March 1983, together with
Gabriel Valdés Subercaseaux, he co-founded the
Democratic Alliance, serving as its president for several periods until 1987. He was also a member of the leadership of the "No" campaign in the 1988 plebiscite. In 1989, together with
Ricardo Núñez, president of the
Socialist Party of Chile, he co-founded the
Party for Democracy (PPD). He was a pre-candidate for the presidency in 1989 and later became president of the presidential campaign committee of
Patricio Aylwin. On 11 March 1990, he was appointed Minister of Foreign Affairs by President Patricio Aylwin, serving until 11 March 1994. During his tenure, he worked to re-establish diplomatic relations with Mexico and countries of Central and Eastern Europe and the former Soviet Union, and promoted regional integration through Chile's incorporation into the
Rio Group, assuming its presidency and pursuing agreements with Bolivia, Argentina, Ecuador, Peru, and other countries on economic, agricultural, and diplomatic matters. ==References==