Encore is the fifth studio album by American rapper Eminem, released on November 12, 2004, through Aftermath Entertainment, Shady Records, and Interscope Records. As reflected in its title, cover art, and certain lyrics, the album was originally set to be Eminem's final studio album. Its lyrical themes include Eminem's criticism of then-U.S. president George W. Bush, parodies of singer Michael Jackson and actor Christopher Reeve, and Eminem's feud with fellow rappers Benzino and Ja Rule. Overall, the album features more comedic themes and lyrics than Eminem's previous albums.

Encore topped the US Billboard 200, selling 710,000 copies, and was certified quadruple platinum by the Recording Industry Association of America (RIAA) just a month after its release. By August of the following year, it had reached sales of 11 million copies worldwide. Encore was met with mixed-to-positive reviews, with many critics deeming it inferior to its three predecessors. Most of the album's middle portion was heavily criticized, though "Like Toy Soldiers" and "Mockingbird" were particularly highly praised and have retrospectively been ranked as some of Eminem's best songs. These two songs were released along with three other singles: "Just Lose It", "Encore", and "Ass Like That". The album was nominated for the Grammy Award for Best Rap Album, but lost.

In retrospect, Eminem has stated that he believes Encore to be one of his worst albums, which he attributed to several songs intended to be part of the album being leaked prior to its official release, requiring him to hastily write and record new ones. These leaked songs were compiled into a bootleg album titled Straight from the Lab. Eminem later revealed that he was also struggling with drug addiction during much of Encore's recording. It would also be Eminem's last studio album until the release of Relapse in 2009.

Prior to producing Encore, American rapper Marshall Bruce Mathers III, better known as Eminem, had released several other studio albums—The Slim Shady LP (1999), The Marshall Mathers LP (2000), and The Eminem Show (2002)—each to critical acclaim. However, Eminem became addicted to a number of drugs during this time, including Valium, Ambien, and Vicodin. In Amsterdam, where a large portion of The Marshall Mathers LP was recorded, Eminem would sometimes take MDMA with his mentor and fellow producer Dr. Dre before an extended recording session. In a cover story celebrating the 25th anniversary of XXL magazine, Eminem stated: "So, I'm coming off The Marshall Mathers LP and going into Encore when my addiction started to get bad. I was taking Vicodin, Valium and alcohol." Eminem specifically recalled an interview alongside hip-hop group G-Unit following their performance in Black Entertainment Television's music video show 106 & Park, in which he was unable to understand any of the questions one of the host asked him, requiring fellow rapper 50 Cent to answer them all for him.

Despite his worsening drug addiction, by 2004, Eminem had won nine Grammy Awards, as well as an Oscar Award for his starring role in the 2002 biographical film 8 Mile. During the time Eminem was recording for Encore in 2003, he was also producing for artists signed to his record label Shady Records, including 50 Cent and Obie Trice. That year, 50 Cent and Trice released their debut studio albums, Get Rich or Die Tryin' and Cheers, respectively, to critical acclaim and commercial success. However, Shady Records inherited a feud between 50 Cent and rapper Ja Rule, as well as Ja Rule's record label, Murder Inc. Records, which had led to multiple diss tracks, including one from Ja Rule in which he mentions Eminem, Dr. Dre, and Eminem's daughter Hailie. Meanwhile, Eminem and his record label were feuding with rapper Benzino and Benzino's hip-hop magazine, The Source, resulting in additional diss tracks. These events are referenced in "Like Toy Soldiers", a song on Encore.

Encore was recorded at 54 Studio in Ferndale, Michigan, a suburb of Detroit, though a portion of the album was recorded at Trans Continental in Orlando, Florida. Eight of the twenty tracks on the album were produced by Dr. Dre, who had produced songs for all of Eminem's albums since The Slim Shady LP. Songwriters Luis Resto, Mike Elizondo, and Mark Batson also produced for the album.

In December 2003, seven songs recorded by Eminem were leaked online, including several songs intended to be part of Encore: "We As Americans", "Bully", and "Love You More". All of these songs were compiled into a bootleg album titled Straight from the Lab. The leak required Eminem to travel to Los Angeles to record new songs for Encore with Dr. Dre. Eminem's worsening drug addiction, coupled with the songs being written in a hurry, resulted in them having a more comedic tone. Eminem has stated that Encore "would've been right there with The Eminem Show as far as its caliber" had the songs not been leaked, and revealed that "We As Americans" was supposed to be the opening track, followed by "Bully". "We As Americans" and "Love You More" were released on the deluxe edition bonus disc. "Bully", a diss track toward Benzino, Ja Rule, and Murder Inc. Records, ultimately would not see an official release.

"Christopher Reeves" was a song originally intended to be the seventh track on the album, though it was cut after its namesake, Superman film actor Christopher Reeve, died of heart failure on October 10, 2004, a month prior to the album's release. The song was later reworked and released 20 years later under the title "Brand New Dance" on Eminem's twelfth studio album, The Death of Slim Shady (Coup de Grâce) (2024).