Vitalogy is the third studio album by American rock band Pearl Jam, released on November 22, 1994, through Epic Records. Pearl Jam wrote and recorded Vitalogy while touring in support of their previous album Vs. (1993). Vitalogy is generally considered to be a departure for the band, incorporating a more diverse range of influences than prior releases; the album features a number of experimental tracks, subdued ballads and punk-influenced hard rock songs.

The album was first released on vinyl, followed by a release on CD and cassette two weeks later on December 6, 1994. The LP sold 34,000 copies in its first week of release, and until Jack White's 2014 album Lazaretto it held the record for most vinyl sales in one week since SoundScan began tracking sales in 1991. Upon its CD release, Vitalogy became the second-fastest selling album in history, behind only the band's previous release Vs., selling 877,000 copies in its first week and quickly going multi-platinum. The album received critical acclaim and has been certified 5× platinum by the Recording Industry Association of America (RIAA) for sales of at least five million copies in the United States. The album was included on Rolling Stone's 2003 and 2012 "500 Greatest Albums of All Time" lists at number 485, but was dropped from the 2020 edition. It is Pearl Jam's second and last album to feature drummer Dave Abbruzzese, who was fired from the band before recording was finished. He was initially replaced by session drummers and later officially replaced by former Red Hot Chili Peppers' drummer Jack Irons, who completed the recording of the album.

For the band's third album, Pearl Jam again worked with producer Brendan O'Brien. The band wrote many of the songs during soundchecks on its Vs. Tour, and the majority of the album's tracks were recorded during breaks on the tour. The first session took place late in 1993 in New Orleans, Louisiana, where the band recorded "Tremor Christ" and "Nothingman". The rest of the material was written and recorded in 1994 in sessions in Seattle, Washington and Atlanta, Georgia, with the band finishing the album at Bad Animals Studio in Seattle after the tour's completion. "Immortality" was written in April 1994 when the band was on tour in Atlanta. Sources state that most of the album was completed by early 1994, but it was not released until November due to either a forced delay by Epic or the band's battle with ticket vendor Ticketmaster.

Tensions within the band had dramatically increased by the time they were working on Vitalogy. Producer Brendan O'Brien said: "Vitalogy was a little strained. I'm being polite—there was some imploding going on." Bassist Jeff Ament said that "communication was at an all-time low". Drummer Dave Abbruzzese stated that the communication problems started once guitarist Stone Gossard stopped acting as the band's mediator. According to Gossard, Vitalogy was the first album for which lead vocalist Eddie Vedder made the final decisions. At the time, Gossard thought of quitting the band. Gossard said the band was having trouble collaborating, so most of the songs were developed out of jam sessions. He added that "80 percent of the songs were written 20 minutes before they were recorded." During the production of Vitalogy, lead guitarist Mike McCready went into rehabilitation to receive treatment for alcohol and cocaine abuse.

Months after finishing the initial recording sessions for Vitalogy, Abbruzzese was fired in August 1994 due to personality conflicts with other band members. Gossard said: "It was the nature of how the politics worked in our band: It was up to me to say, 'Hey, we tried, it's not working; time to move on.' On a superficial level, it was a political struggle: For whatever reason, his ability to communicate with Ed and Jeff was very stifled. I certainly don't think it was all Dave Abbruzzese's fault that it was stifled." Jack Irons, the original drummer for the Red Hot Chili Peppers and Abbruzzese's successor, plays drums on "Hey Foxymophandlemama, That's Me". Gossard said: "Jack entered the band right at the end of making Vitalogy. Jack's a breath of fresh air, a family man. Everybody had a strong sense of friendship with him immediately. He was just there to play drums and help out."

Overall, Vitalogy has been identified as a punk rock album by both critics and members of Pearl Jam, departing the grunge sound of the band's previous work. Despite this, some publications have labeled the album as grunge.

In a 1995 interview, Guitar World writer Jeff Gilbert described Vitalogy as "strange" and "very eclectic". McCready agreed, saying: "There is some weird stuff on there." McCready attributed the album's sound to the group recording it on tour. During this period Vedder began to contribute in a large capacity as a guitarist. Gossard said: "Vitalogy is the first one where Ed plays guitar and he wrote three to four songs. I remember thinking, 'This is so different. Is anyone going to like this?'...It had a more punk feel to it. Simple songs recorded really quickly." The album has a notable lack of guitar solos compared with the band's first two albums. McCready said: "Vitalogy is not really a 'solo' album. I don't think the songs demanded solos; it was more of a rhythmic album."

Stephen Thomas Erlewine of AllMusic said that "thanks to its stripped-down, lean production, Vitalogy stands as Pearl Jam's most original and uncompromising album." He added that "in between the straight rock numbers and the searching slow songs, Pearl Jam contribute their strangest music—the mantrafunk of 'Aye Davanita', the sub-Tom Waits accordion romp of 'Bugs', and the chilling sonic collage 'Hey Foxymophandlemama, That's Me'." "Bugs" features Vedder playing an accordion that he found at a thrift shop, while "Hey Foxymophandlemama, That's Me" was created using looped recordings of real patients from a psychiatric hospital. Tim Coffman of WhatCulture considers Vitalogy to be a delve into art rock, commenting that the band "[threw] every outlandish idea into the mix."