Known as a versatile character actress, Smart has worked stage and screen but found the bulk of her success on television. After college graduation, she performed in regional theater before heading to Broadway and eventually landing the role of Marlene Dietrich in the play Piaf. The show was later brought her to Hollywood when it was reprised for TV and earned Smart wider exposure. The hit sitcom Designing Women jumpstarted her career in 1986 and introduced her to costar and future husband Richard Gilliland. Smart was 40 when she left the series to try her luck in movies. She was scarily convincing as serial killer Aileen Wuornos in Overkill, years before Charlize Theron snagged an Oscar for playing the same part in Monster. In 2001 she was nominated for two Emmys, for a dramatic role on The District and a hilariously harsh turn on Frasier, which won her a statuette. While her movie career heated up with high-profile supporting parts in Bringing Down the House and Garden State, it was her harrowing turn as the president's emotionally unstable wife on 24 that once again had people talking. Smart devotes her free time to juvenile diabetes education (she was diagnosed herself at age 13) and the Alzheimer's Association (having lost her father to the disease).
- Diagnosed as diabetic at age 13 and lost her father to Alzheimer's disease; as an adult, became active in juvenile diabetes education and the Alzheimer's Association.
- Began career as a stage performer in regional theater and made Broadway debut in 1981 in the play Piaf portraying Marlene Dietrich.
- Shot to TV success as Charlene Frazier on five seasons of Designing Women. Met and married Richard Gilliland while working on that series, where he had a recurring role as J.D. Shackleford.
- To show versatility and avoid being typecast followed the sitcom by playing the serial killer and title character in the biopic Overkill: The Aileen Wuornos Story.
- Her portrayal of the emotionally fragile First Lady Martha Logan on the action-suspense drama 24 was inspired by Martha Mitchell, wife of U.S. Attorney General John Mitchell during the Watergate scandal.
- 2000, Emmy — Outstanding Guest Actress in a Comedy Series: Winner
- 2001, Emmy — Outstanding Guest Actress in a Drama Series: Nominee
- 2001, Emmy — Outstanding Guest Actress in a Comedy Series: Winner
- 2006, Emmy — Outstanding Supporting Actress in a Drama Series: Nominee
- 2001, Tony — Actress (Play): Nominee
- 2007, Emmy — Outstanding Guest Actress in a Drama Series: Nominee
- 2008, Emmy — Outstanding Supporting Actress in a Comedy Series: Winner
- 2006, Screen Actors Guild Awards — Outstanding Performance by an Ensemble in a Drama Series: Nominee
- 2012, Emmy — Outstanding Guest Actress in a Drama Series: Nominee
- 2000, Independent Spirit Awards — Best Supporting Female: Nominee
- 2016, Emmy — Outstanding Supporting Actress In A Limited Series Or A Movie: Nominee
- 2016, Critics' Choice Awards — Best Supporting Actress in a Movie Made for Television or Limited Series: Winner
- Connor Douglas Gilliland — Son
- Douglas Smart — Father
- Richard Gilliland — Husband
- Kay Smart — Mother
- Bonnie Kathleen Gilliland — Daughter
- University of Washington, Seattle, WA (BA in Fine Arts)
- Birth Place: Seattle, WA
- Birthday: September 13, 1951, Virgo
- Profession: Actor