Born and raised in Kentucky, Sawyer followed in her older sister's wake, participating in beauty pageants. In 1963, she was crowned America's Junior Miss, earning a scholarship that allowed her to attend Wellesley College in Massachusetts. After graduation, Sawyer planned to attend law school, but decided to pursue a career in broadcasting. Her first assignment was as a "weather girl" on WLKY-TV in Louisville in 1967. Spending three years with the station, she was able to become a news reporter. The daughter of a Republican county judge, she left WLKY in 1970 to become an aide to Presidential press secretary Ron Ziegler in Richard Nixon's administration. When Nixon resigned in 1974, Sawyer was one of the staff members who went with him into "exile" in San Clemente, California, helping the former chief executive organize his memoirs. The connection with Nixon caused some rumblings when CBS News hired Sawyer in 1978 as a reporter. Yet, Sawyer proved herself and by the early 80s was covering the State Department. From 1981 to 1984, she was co-anchor of "CBS This Morning", an early-morning news program, before joining "60 Minutes" as its first female correspondent.

In 1989, Sawyer was lured away to ABC with a reported $1.5 million salary and the promise of anchoring her own newsmagazine. "PrimeTime Live" debuted on August 3, 1989 and found her teamed with Sam Donaldson. At first, the pair showed no chemistry, but ABC re-formatted and stuck with the show. While not the highest-rated newsmagazine on the air, "PrimeTime Live" has had its strong individual installments and has remained competitive. Sawyer not only serves as an anchor the show, but also handles at least 40 percent of the stories. She has used hidden cameras to reveal racial discrimination in America, conducted interviews with Fidel Castro and Manuel Noriega, and also was the first news reporter to interview Patricia Bowman, the woman who accused William Kennedy Smith of rape. In particular, Sawyer has won Emmy Awards for the coverage of the Pan Am Flight 103 tragedy and the story of the Menendez Brothers in the early stages of the case. In 1994, Sawyer signed a five-year contract with ABC News reported to be worth $7 million. Two years later, ABC renewed "PrimeTime Live" on its Wednesday night schedule for the fall, and also made "Turning Point", which Sawyer has anchored as occasional specials, into a Thursday night weekly series. Her "Turning Point" specials have included "Baby, Oh Baby: The Six Pack Is Back", a 1996 effort focusing on families with multiple births after using fertility drugs.

While Sawyer keeps a low profile off-the-airwaves, her marriage to celebrated director Mike Nichols has kept her in a constant spotlight. Sawyer is one of the most photographed news anchors in TV, whether she seeks to be or not.