During his long political career, Colombo held many offices in several governments. He served as Minister of Agriculture from 1955 to 1958; Minister of Foreign Trade from 1958 to 1959; Minister of Grace and Justice from 1970 to 1972; Minister of Treasury from 1963 to 1970, in 1962 and from 1974 to 1976; Minister of Budget in 1968 and from 1987 to 1988; Minister of Finance from 1988 to 1989; Minister of Foreign Affairs from 1980 to 1993 and from 1992 to 1993. Colombo, a fervent Europeanist, served also as President of the European Parliament from 1977 to 1979.