
Jay Scott Greenspan (born September 23, 1959), better known by his professional name of Jason Alexander, is an American actor, writer, comedian, television director and producer, and singer. He is best known for his role as George Costanza on the television series Seinfeld, appearing in the sitcom from 1989 to 1998. He also has had an active career on the stage, appearing in several Broadway musicals including Jerome Robbins' Broadway in 1989, for which he won the Tony Award as Best Actor in a Musical. He appeared in the Los Angeles production of The Producers with Martin Short. He is the Artistic Director of "Reprise! Broadway's Best in Los Angeles," where he has directed several musicals. Alexander is also an avid poker player.

The Simpsons
TV • 1989

Criminal Minds
TV • 2005

American Dad!
TV • 2005

American Dad!
TV • 2005

Community
TV • 2009

Late Night with Seth Meyers
TV • 2014

Friends
TV • 1994

Saturday Night Live
TV • 1975

Saturday Night Live
TV • 1975

Seinfeld
TV • 1989

The Late Late Show with Craig Ferguson
TV • 2005

Monk
TV • 2002

Two and a Half Men
TV • 2003

Golden Globe Awards
TV • 1944

Real Time with Bill Maher
TV • 2003

Young Sheldon
TV • 2017

Star Trek: Voyager
TV • 1995

The Late Late Show with James Corden
TV • 2015