Brennan joined CBS News in July 2012.
Since 2012, she was based in Washington and reported on the White House across the Obama and Trump administrations for CBS programs.
She substitute anchors on CBS This Morning and the CBS Evening News.
Brennan was also part of the CBS News team honored with a 2012-2013 Alfred I. Dupont-Columbia Award for coverage of the Newtown tragedy.

Brennan's reporting has taken her to Tehran, Baghdad, Kabul, Beijing, and Havana.
She has covered diplomatic negotiations including the nuclear deal with Iran, the chemical weapons deal in Syria, and the reopening of relations with Cuba.

She conducted the first US interview with South Korean President Park Geun-Hye covering her hardline policy against North Korea.

The interview made headlines in Pyongyang and Seoul, where her etiquette was the topic of a morning show.

She was also among the first reporters to interview Hillary Clinton about the fatal attack on the US mission in Benghazi, Libya.

At a press conference on September 9, 2013, she asked Secretary of State John Kerry about any possibility for the Syrian government to avoid a U.S. strike.
Kerry answered that Assad could "turn over every single bit of his chemical weapons to the international community in the next week"—although later his answer was retracted as "a rhetorical argument about the impossibility and unlikelihood of Assad turning over chemical weapons he has denied using" by a State Department spokesperson—led Russia's foreign minister Sergey V. Lavrov to propose this as a solution to the crisis.

On February 22, 2018, she was named the 10th moderator of Face the Nation, the network's Sunday morning political interview show, becoming only the second woman to moderate the program.
Brennan joined CBS News in July 2012. Since 2012, she was based in Washington and reported on the White House across the Obama and Trump administrations for CBS programs. She substitute anchors on CBS This Morning and the CBS Evening News. Brennan was also part of the CBS News team honored with a 2012-2013 Alfred I. Dupont-Columbia Award for coverage of the Newtown tragedy.
Brennan's reporting has taken her to Tehran, Baghdad, Kabul, Beijing, and Havana. She has covered diplomatic negotiations including the nuclear deal with Iran, the chemical weapons deal in Syria, and the reopening of relations with Cuba. 
She conducted the first US interview with South Korean President Park Geun-Hye covering her hardline policy against North Korea.
The interview made headlines in Pyongyang and Seoul, where her etiquette was the topic of a morning show.
She was also among the first reporters to interview Hillary Clinton about the fatal attack on the US mission in Benghazi, Libya.
At a press conference on September 9, 2013, she asked Secretary of State John Kerry about any possibility for the Syrian government to avoid a U.S. strike. Kerry answered that Assad could "turn over every single bit of his chemical weapons to the international community in the next week"—although later his answer was retracted as "a rhetorical argument about the impossibility and unlikelihood of Assad turning over chemical weapons he has denied using" by a State Department spokesperson—led Russia's foreign minister Sergey V. Lavrov to propose this as a solution to the crisis.
On February 22, 2018, she was named the 10th moderator of Face the Nation, the network's Sunday morning political interview show, becoming only the second woman to moderate the program.
Margaret Brennan