Achtung Baby is the seventh studio album by Irish rock band U2, released on 19 November 1991. Stung by criticism of their previous album, Rattle and Hum, the album was a calculated change in musical and thematic direction with the incorporation of alternative rock, electronic dance music, and industrial influences. It was the band's most dramatic change since The Unforgettable Fire album.
Seeking renewal and inspiration on the eve of German reunification, the band began work on Achtung Baby in Berlin's Hansa Studios in October 1990 with producers Daniel Lanois and Brian Eno. Conflict arose within the band over the quality of the material and their musical direction. Weeks of slow progress, arguments, and tension subsided when the band quickly improvised the song "One", which was a breakthrough for the album sessions. The band was more productive in the studio after recording sessions moved to Dublin in 1991.
Sonically, the band referred to the album as the sound of "four men chopping down the Joshua Tree". Thematically, it was a more inward-looking and personal record; it was darker, yet more playful than the band's previous work. Commercially and critically, Achtung Baby has been one of the band's most successful albums. It produced several hit singles in One, "Mysterious Ways", and "The Fly", has sold 18 million copies worldwide, and won a Grammy Award. The album and the subsequent multimedia-intensive Zoo TV Tour were a crucial part of the band's 1990s reinvention. In 2003, the album was ranked number 62 on Rolling Stone magazine's list of "The 500 Greatest Albums of All Time".