[2] He began working for the Customs and Economic Union of Central Africa (UDEAC) in the 1970s, then became Director-General of the Union Bank in Central Africa, located in Bangui, before being dismissed from that post by President André Kolingba in 1981.

Kolingba moved Gaombalet to a position at the Development Bank of Central African States in Brazzaville.

[3] Despite having no political experience,[3] Gaombalet was appointed as prime minister by President François Bozizé on December 12, 2003, replacing Abel Goumba, who in turn became Bozizé's vice-president.

[4] In a reshuffle of the government on September 2, 2004, Gaombalet remained prime minister while the number of ministers was reduced to 24 from the previous 28; Gaombalet said that this did not affect the political balance and that it was necessary to save money.

At the opening of the National Assembly, he was elected as President of the National Assembly on June 7, 2005, receiving 78 votes against 18 for Luc Apollinaire Dondon Konamabaye, who had previously held the position under President Ange-Félix Patassé.