[2] He was named editor-in-chief of La Tarde, one of a number of periodicals owned by his father, in 1976, and steered the daily in support of the newly installed dictatorship.

He served as a director of the Buenos Aires office of the Permanent Assembly for Human Rights from 2002 to 2004, and was President of the International Coalition of Historic Site Museums of Conscience.

Timerman was the first witness to give testimony in the trial of Christian von Wernich, a former Buenos Aires Province Police chaplain convicted of complicity in numerous dictatorship-era murders and tortures (including that of his father).

[4] President Néstor Kirchner appointed Timerman Consul General in New York City in July 2004, and in December 2007, he was named Argentine Ambassador to the United States.

Bringing perpetrators of the 1994 AMIA bombing to justice was prioritized, pursuant to which he persuaded the neighboring government of Bolivia to cut short a state visit to that country in 2011 by Iranian Defense Minister Ahmad Vahidi (whose arrest Argentine authorities had sought since 2007 in connection with the attack),[9] while also working to establish a Truth Commission jointly with Iran in 2013 to investigate the 1994 bombing.

"[13] His policy regarding the dispute remained assertive, refusing to accept a letter from a member of the Legislative Assembly of the Falkland Islands who ambushed Timerman following talks in February 2013 with U.K. Foreign Secretary William Hague,[14] obtaining declarations in support of Argentine sovereignty from African and Latin American nations,[15] and later declaring that the Falklands "will be under our control within 20 years.