Christine Jane Baranski (born May 2, 1952) is an American actress, notable for her extensive work in the film, television, and theatre industries. She is best known for her portrayal of Maryann Thorpe in the sitcom Cybill (1995–1998), which earned her a Primetime Emmy Award for Outstanding Supporting Actress in a Comedy Series. Baranski also gained recognition for her roles as Diane Lockhart in the legal drama series The Good Wife (2009–2016) and its spin-off series The Good Fight (2017–2022), as well as Agnes van Rhijn in the period drama series The Gilded Age (2022–present). Besides these notable television roles, Baranski has also made a considerable impact in the film industry with roles in Reversal of Fortune (1990), The Birdcage (1996), Cruel Intentions (1999) and Mamma Mia! (2008), among others. On the stage, she is a two-time Tony Award recipient for her performances in Tom Stoppard's The Real Thing (1984) and Neil Simon's Rumors (1989). Other significant Broadway credits include Hurlyburly (1984), The House of Blue Leaves (1986), and Boeing Boeing (2008).

Baranski was born in Buffalo, New York to parents Virginia and Lucien Baranski. She is of Polish descent and has a deep cultural connection to her roots. Her early upbringing was in a firmly Polish and Catholic neighborhood in the Buffalo suburb of Cheektowaga. She attended high school at the Villa Maria Academy. Subsequently, she moved to New York City to study at the prestigious Juilliard School where she graduated with a Bachelor of Fine Arts degree. Her acting career, spanning over four decades, started in earnest in the early 70s. She made both her off-Broadway and Broadway debut in 1980 and has since then enjoyed a steady rise of success across the different performance platforms. Notable among these was her performance as Dr. Beverly Hofstadter in the popular sitcom The Big Bang Theory (2009–2019), for which she received four Primetime Emmy nominations. Building her portfolio as a versatile and globally recognized actress, Baranski continues to impact the entertainment world with her distinctive on-screen persona and impressive range of roles.