He made his acting debut in an off-Broadway theater in 1995, in The Monogamist, and won the Theatre World Award for his performance, and then originated David Sedaris' The Santaland Diaries in 1996.

He had starring roles in films such as Catch and Release (2006), Hitman (2007), A Perfect Getaway (2009), and The Crazies (2010), and he played the main antagonist, Thomas Gabriel, in Live Free or Die Hard (2007).

Marshal Raylan Givens in FX's modern-day Kentucky southern gothic Justified, a performance for which he was nominated for a Primetime Emmy Award for Outstanding Lead Actor in a Drama Series in 2011.

[43] He starred in the world premiere of The SantaLand Diaries (1996) at the Atlantic Theater Company, a one-man play based on David Sedaris' essay about working as a Macy's department store Christmas elf.

"[47] Olyphant made his feature film debut in The First Wives Club (1996) as an eager young director who attempts to cast Elise Elliot (Goldie Hawn) – who thinks she will be playing the leading lady – in the role of the elderly mother.

[49][50] In 1997, Olyphant made a guest appearance as Officer Brett Farraday in three episodes of the ABC police drama High Incident[51] and returned to New York's Playwrights Horizons to play a supporting role in Plunge.

"[56] Olyphant returned to television in 1998 for a guest starring role in an episode of the HBO sitcom Sex and the City, playing a love interest for Carrie Bradshaw.

[59][60] Two little-seen films were released in 1999: the drama Advice from a Caterpillar, in which Olyphant played the bisexual love interest of Cynthia Nixon's character,[61][62] and the offbeat ensemble comedy No Vacancy, in which he starred with Christina Ricci.

[68][69] After Olyphant's performance in Go, the film's producer Mickey Liddell offered him his choice of parts in his next project The Broken Hearts Club (2000), a romantic comedy about a group of gay friends living in West Hollywood.

Kevin Crust of the Los Angeles Times wrote that he "possesses the kind of thousand-yard stare that suggests something deeper going on,"[86] while Owen Gleiberman of Entertainment Weekly remarked that "Olyphant, in the sort of role that Paul Newman used to swagger through, has a star's easy command.

Desson Howe of the Washington Post remarked that Olyphant "gets a kudo or two for [having] the good sense to realize he's playing one of the movie's many one-dimensional characters, so he might as well have insane fun".

[89] Similarly, Mick LaSalle of the San Francisco Chronicle noted that "the most lively character in "A Man Apart" turns out [to be] a middling drug dealer played to the hilt by Timothy Olyphant.

[91][92][93] The film was poorly reviewed, with David Rooney of Variety remarking: "Only Lee and Olyphant come close to hitting the right note of tongue-in-cheek humor that might have made all this palatable.

"[75] Mick LaSalle of the San Francisco Chronicle described the character of Kelly as "a leering, magnetic, frightening, glad-handing, easily-amused, hyper-sensitive, utterly deceitful, maddeningly likable wild man.

[104] In a 2015 interview, Olyphant reflected on the early stages of his film career, and not getting the leading roles that would have possibly led to major fame: "I got great opportunities right off the bat.

[75] While he had previously been typecast "as a talkative, Jack Nicholson–styled, funny bad boy," in the words of Vulture's Matt Zoller Seitz,[106][107] Deadwood gave him the opportunity to play a righteous, brooding lawman.

[7][53][121] Lael Loewenstein of Variety felt "Olyphant clearly has a bright future"[122] while Desson Thomson of the Washington Post described him as "the strongest performer here" but that he was "entirely misplaced, an estimable actor caught in a thankless, frilly role".

[131][132][133] Peter Travers of Rolling Stone declared him "a master at smiling menace",[134] while Mick LaSalle of The San Francisco Chronicle found him "perfectly ice cold".

[145] In 2008, he had a supporting role as a lieutenant colonel in the Iraq War drama Stop-Loss,[53][146] played a pompous newscaster in the little-seen comedy Meet Bill,[147] voiced the character Cowboy in the video game Turok[148] and made a guest appearance on the first season of the ABC sitcom Samantha Who?

[151][168] Peter Bradshaw of The Guardian was impressed by the "saturnine screen presence of Timothy Olyphant – that formidable actor who deserves a lead role to match his potential.

[64][181][182] Brian Lowry of Variety said it was "an unabashed star turn": "There are surely worse ways to be pigeonholed than playing tough, laconic lawmen, and Timothy Olyphant is carving himself a formidable niche in those confines ...

"[183] Tim Goodman of the San Francisco Chronicle praised "an incredibly riveting performance": "Olyphant's steely gaze, Zen interior and matinee looks called to mind a younger Clint Eastwood.

"[185] Matthew Gilbert of The Boston Globe said: "It's hard to imagine any other actor in the part, as Olyphant milks Raylan's smooth, laconic cowboy style for as much wry humor as he can.

He played a paper salesman in two episodes of the NBC comedy The Office (2010), after Mindy Kaling, a writer, producer and actress on the show, pushed for him to make a guest appearance.

[206][207] The character was a parody of Clint Eastwood's Man with No Name[208] and Olyphant was cast after director Gore Verbinski overheard him speaking on television: "I just sort of doubled back and looked through the door and was like, "That's our guy" ... Timothy has such a great quality to his voice.

The film received mixed reviews,[218] with David Edelstein of Vulture commenting: "Over the course of his career, Olyphant has given life to head-slappingly bad material, and he does it again by simply underplaying.

[226][227] Ben Brantley of the New York Times found him "entertainingly irritating" in a performance that "avoids the obvious route of histrionic posing"; "The startling, bona fide sorrow that Mr. Olyphant brings to [the final scene] truly illuminates everything that has come before.

"[228] Frank Rizzo of Variety felt his performance was "a stunner, striking just the right notes of guilelessness, obliviousness and narcissism to make Strings one of the most appealing messes in a long time".

[229] David Rooney of The Hollywood Reporter felt the role "seems tailor-made for his laid-back swagger and sly humor ... Olyphant's natural charm ensures that Strings' unapologetic self-absorption remains more human than monstrous.

[232] In February 2017, Olyphant began starring in the Netflix horror-comedy Santa Clarita Diet, and also served as an executive producer for the series, which co-starred Drew Barrymore.