Greenfield was hired as a
speechwriter for the 1968 presidential campaign of Senator
Robert F. Kennedy. Greenfield assisted with RFK's speech, "
On the Mindless Menace of Violence", that he delivered the day after
Martin Luther King Jr.'s assassination. Greenfield was chief speechwriter for New York City Mayor
John Lindsay and also worked for seven years with political consultant David Garth. Over the course of his journalistic career, Greenfield has reported mainly on domestic politics and the media, with occasional pieces on cultural matters. He appeared on the
Firing Line television program as early as 1968. For five seasons, he hosted the national public television series "
CEO Exchange" where he featured in-depth interviews with high-profile chief executive officers. He served as media commentator for
CBS News from 1979 to 1983 and as political and media analyst for
ABC News from 1983 to 1997, often appearing on the
Nightline program. He was a senior analyst at
CNN from 1998 to 2007. On May 1, 2007, Greenfield returned to CBS News, where he served as a senior political correspondent until April 2011. He hosted PBS's "Need to Know" from May 7, 2010, to June 28, 2013. More recently he has done political commentary on
NBC Nightly News. He has also authored or contributed to fourteen books and has written for
Time,
The New York Times,
National Lampoon,
Slate, and
POLITICO Magazine. He wrote one novel, ''
The People's Choice'', with a plot that centers on the Electoral College. Greenfield has won five
Emmy Awards, two for his reporting from South Africa (1985 and 1990) and one for a profile of
H. Ross Perot (1992). His bestseller
Then Everything Changed was a finalist for the 2011
Sidewise Award for Alternate History, Long Form. In the fall of 2020, Greenfield served as a Fellow at the
USC Center for the Political Future. There, he led a study group discussing political media in the United States. ==Personal life==