George Clooney as Michael Clayton

Tom Wilkinson as Arthur Edens

Tilda Swinton as Karen Crowder

Michael O'Keefe as Barry Grissom

Sydney Pollack as Marty Bach

Danielle Skraastad as Bridget Klein (voice)

Wai Chan as Chinese Dealer

Alberto Vazquez as Player #1

Brian Koppelman as Player #2

Tom McCarthy as Waiter (voice)

Denis O'Hare as Mr. Greer

Julie White as Mrs. Greer

Austin Williams as Henry Clayton

Jennifer Van Dyck as Ivy

Frank Wood as Gerald

Richard Hecht as Auctioneer

Bill Raymond as Gabe Zabel

Jonathan Walker as Del (voice)

Sharon Washington as Pam

Cynthia Mace as Wendy (voice)

Michael Countryman as Evan (voice)

Ken Howard as Don Jeffries

Amy Hargreaves as Interviewer

Susan Pellegrino as Secretary

Rachel Black as Maude

Matthew Detmer as Todd

John Douglas Thompson as Jail Guard

Merritt Wever as Anna

Brian Poteat as Deposition Lawyer

Christopher Mann as Lieutenant Elston

Edward Furs as Milwaukee Captain

Katherine Waterston as Third Year

John Gerard Franklin as Correction Officer

Remy Auberjonois as Fifth Year

Pun Bandhu as Fourth Year

Jason Strong as First Year

Robert Prescott as Mr. Verne

Paul Oquist as Starter

Terry Serpico as Mr. Iker

Heidi Armbruster as Anna's Sister

Pamela Gray as Cindy Bach

Andrew Hunter Sherman as U / North (voice)

Kevin Hagan as Raymond Clayton

Julia Gibson as Stephanie Clayton

Sean Cullen as Gene Clayton

Susan Egbert as Michelle

David Lansbury as Timmy Clayton

David Zayas as Detective Dalberto

Douglas McGrath as Jeff Gaffney

Gregory Dann as Cop

Cathy Diane Tomlin as Cop #2

Sam Gilroy as Copy Kid

Maggie Siff as Attorney #1

Sarah Nichols as Barry's Assistant

Susan McBrien as Jean

Jordan Lage as Partner

Neal Huff as First Associate

Paul Juhn as Second Associate

Patrick Askin as Auction Bidder (uncredited)

Angelo Bonsignore as Videographer (uncredited)

Kevin Cannon as Auction Worker (uncredited)

Clem Cheung as Landlord (uncredited)

Tony Gilroy as Taxi Driver (voice) (uncredited)

Emelie Jeffries as Raymond Clayton's Nurse (uncredited)

Josh Mowery as Lawyer (uncredited)

Kimmy Suzuki as Copy Shop Clerk (uncredited)

Steven Weisz as Executive (uncredited)