Jason Alexander (born September 23, 1959) is an award winning American television, cinema and musical theatre actor, perhaps best known for his role as George Costanza on the hit television series Seinfeld.
Jason Greenspan adopted the stage name Jason Alexander while still in high school in New Jersey. He was soon appearing in Broadway plays and movies, then in the hit TV series, "Seinfeld" (1990), from 1990 to 1998. Alexander also directs and produces films.