Prior to being appointed Ambassador to the United States, Ambassador Mauro Vieira was the Brazilian Ambassador to Argentina since 2004. He holds a JD from the Federal University of Rio de Janeiro and graduated from Instituto Rio-Branco, the Brazilian diplomatic academy.

At the Brazilian Ministry of Foreign Relations, Ambassador Vieira has had several positions, including Chief of Staff to the Secretary-General, and Chief of Staff to the Minister of External Relations. From January 2003 to May 2006, he was the representative of the Brazilian Ministry of External Relations to the Board of Directors of Itaipu Binacional hydroelectric power plant.

Ambassador Vieira has also held positions at other Brazilian federal agencies, having served as Secretary for Managerial Modernization at the Ministry of Science and Technology, Assistant Secretary-General for Science and Technology, and National Secretary for Management at the National Institute for Social Security at the Ministry of Social Security and Assistance.

Abroad, Ambassador Vieira served at the Embassy in Washington (1978-1982); the Mission to the Latin American Integration Association (ALADI) in Montevideo (1982-1985); the Embassy in Mexico City (1990-1992); and the Embassy in Paris (1995-1999).

Ambassador Mauro Vieira has received decorations from the governments of Brazil, Argentina, Chile, Peru, Mexico, Portugal, Spain, France, Denmark, Norway, the Netherlands, Poland, and Romania.

He was born in Niterói, state of Rio de Janeiro, on February 15, 1952.