Margaret JoBeth Williams is an American actress. She rose to prominence appearing in such films as Kramer vs. Kramer (1979), Stir Crazy (1980), Poltergeist (1982), The Big Chill (1983), The Day After (1983), Teachers (1984), and Poltergeist II: The Other Side (1986). A three-time Emmy Award nominee, she was nominated for Outstanding Lead Actress in a Miniseries or a Movie for her work in the TV movie Adam (1983) and the TV miniseries Baby M (1988). Her third nomination was for her guest role in the sitcom Frasier (1994). She also starred in the TV series The Client (1995–96) and had recurring roles in the TV series Dexter (2007) and Private Practice (2009–11).

Kramer vs. Kramer is a 1979 American legal drama written and directed by Robert Benton, based on Avery Corman's 1977 novel of the same name. The film stars Dustin Hoffman, Meryl Streep, Justin Henry and Jane Alexander. It tells the story of a couple's divorce, its impact on their young son, and the subsequent evolution of their relationship and views on parenting.