Andrew Klavan, (born 1954), also known by his pen name Keith Peterson, is an American writer of mystery novels, psychological thrillers, and screenplays for "tough-guy" mystery films. Two of Klavan's books have been adapted into motion pictures: True Crime (1999) and Don't Say a Word (2001). He has been nominated for the Edgar Award four times and has won twice. Playwright and novelist Laurence Klavan is his brother.