In 1969, newly-elected president Rafael Caldera appointed Oberto as Minister of Planning [es]; in this position, the U.S. Department of State considered him to be one of Venezuela's most senior government officials.

Oberto resigned as Minister of Finance in 1974 following the election of President Carlos Andrés Pérez.

In 1974, Oberto served as a member of the Presidential Commission for Oil Reversal, and later that year, he became an advisor for the Inter-American Development Bank.

[6] In 1978, Oberto, a member of COPEI, was elected to the Chamber of Deputies where he subsequently served for the following twenty years.

From 1998 until 2000, Oberto served as the president of the National Academy of Economic Sciences, an institution he founded in 1982.

Oberto served as a member of the board of directors of the Institute of Advanced Studies in Administration from 2000 to 2003.