Founder of the Brazilian Center for International Relations (CEBRI). Ambassador Fonseca was a career diplomat between 1968 and 2016, when he retired. Today he is Director of the Center for History and Diplomatic Documentation (CHDD) of the Alexandre de Gusmão Foundation (FUNAG).

He was previously Permanent Representative to the United Nations in New York (1999-2003), Ambassador to Chile (2003-2006) and Consul General in Madrid (2006-2009) and Porto (2012-2016). He served in various capacities in Brazil, at the office of the President of the Republic and in the State Department, where his most recent position was as Inspector General of Foreign Service. He was Professor of International Relations Theory at the Rio Branco Institute between 1980 and 1998.

Ambassador Fonseca received a Bachelor of Law from Guanabara State University (now UERJ) and a Master of Arts degree in Latin American Studies from Georgetown University. He holds a PhD in International Relations from the Federal University of Rio Grande do Sul.  He has numerous publications on international issues.