Selma Blair Beitner (born June 23, 1972) is an American actress. Blair's best known film roles were in Cruel Intentions (1999), which also starred Sarah Michelle Gellar, and Legally Blonde. More recently she appeared alongside Cameron Diaz and Christina Applegate in The Sweetest Thing (2002), and in Hellboy (2004).

She was born to a Jewish family in Southfield, Michigan with the Hebrew name Batsheva, and as a child attended Hillel Day School and Cranbrook Kingswood school near Detroit, Michigan. She studied at Kalamazoo College from 1990–1992, then transferred to the University of Michigan, where she earned her bachelor's degree in 1994. She also attended the Stella Adler Acting School.

She has been married to Ahmet Zappa since 24 January, 2004.