Since joining ABC News in 2003, Muir has reported from international hotspots all over the world, with dispatches from Afghanistan, Iraq, Iran, Ukraine, Tahrir Square, Mogadishu, Gaza, Guantanamo, Fukushima, Beirut, Amman, and the Syrian border, among other locations.

[1] At ABC News, Muir has won multiple Emmy and Edward R. Murrow awards for his national and international journalism.

As a child, he watched ABC News' flagship program each night with his family and credits longtime anchor Peter Jennings as his biggest journalistic influence.

He attended Ithaca College, graduating magna cum laude with a Bachelor of Arts degree in journalism in May 1995.

[12] Muir's reports from Jerusalem, Tel Aviv, Israel, and the Gaza Strip following the 1995 assassination of Israeli Prime Minister Yitzhak Rabin earned him top honors from the Radio-Television News Directors Association.

In April 2009, David Muir and Diane Sawyer reported a 20/20 hour about guns in America getting "disturbing results" as described by the New York Daily News.

In January 2010, Muir traveled to Haiti in the wake of the devastating earthquake, which orphaned tens of thousands of children and destroyed the country's buildings and basic services.

[19] He has returned to Haiti multiple times since the earthquake hit, uncovering attacks on women and the unfolding mental health crisis in Port au Prince.

[20] In June 2011, Muir reported from Tahrir Square during the political revolution in Egypt, and from Fukushima, Japan following the deadly tsunami and nuclear power plant accident.

[22] Muir's interviews with Republican candidate Mitt Romney generated national headlines on the issues of economics and immigration policy in the United States.

[23][24] In December 2012, Muir also anchored several hours of the Sandy Hook Elementary School shooting as it unfolded, and then reported from the scene as President Obama visited the town.

[28][29] Muir has brought the series to other television programs, including ABC's The View, where he has served as guest co-host.

During one of Muir's interviews with Secretary of State Hillary Clinton in 2015, she admitted it was a mistake to use a private e-mail server and offered her first apology to the American people.

[37] Ahead of the 2020 presidential election, Muir conducted the first joint interview with Democratic nominee Joe Biden and his running mate, then-Senator Kamala Harris.

[40] Muir was the first network anchor to interview Ukrainian President Volodymyr Zelenskyy after the Russian invasion of Ukraine.

Muir’s and Davis's interjections sparked claims of bias from Trump and Republicans and discussion over the role of moderators in presidential debates.