John M. Slattery, Jr. (born August 13, 1962) is an American actor and director, best known for his roles as Roger Sterling on AMC's series Mad Men, Frank Jaffe in Confess, Fletch, Howard Stark (Tony Stark's father) in the Marvel movie series, Paul LeBlanc on FOX's NEXT, Dwight Eisenhower in Churchill, Lyle Bettencourt on CBS's The Good Fight, Richardson in The Adjustment Bureau, Cravely in Charlie Wilson's War, Bud Gerber in Flags of Our Fathers, Peter Benedict on WB's Jack & Bobby, Roland Yates in Bad Company, Dr. Richard Meyers on Lifetime's sitcom Maggie, FBI Agent Corman in Eraser, and Al Kahn on ABC's Homefront.

He has been married to actress Talia Balsam since 1998 and they have a son, Henry.