Katherine Whitton Baker (born June 8, 1950) is an American stage, film and television actress.

Baker began her career in theatre and made her screen debut in the 1983 drama film, The Right Stuff. She received the National Society of Film Critics Award for Best Supporting Actress and an Independent Spirit Award nomination for her performance in Street Smart (1987). Baker also has appeared in over 50 films, including Jacknife (1989), Edward Scissorhands (1990), The Cider House Rules (1999), Cold Mountain (2003), Nine Lives (2005), The Jane Austen Book Club (2007), Last Chance Harvey (2008), Take Shelter (2011), Saving Mr. Banks (2013) and The Age of Adaline (2015).

On television, Baker starred as Dr. Jill Brock in the CBS drama series, Picket Fences (1992-1996), for which she received three Primetime Emmy Award for Outstanding Lead Actress in a Drama Series and Golden Globe and Screen Actors Guild Awards. She later received three additional nominations and a Primetime Emmy Award for her performances in Touched by an Angel, Boston Public and Door to Door.