Mob Rules is the tenth studio album by English rock band Black Sabbath, released in November 1981.

It followed 1980's Heaven and Hell, and was the second album to feature lead singer Ronnie James Dio and the first with drummer Vinny Appice.

The first new recording Black Sabbath made after the Heaven and Hell album was a version of the title track "The Mob Rules" for the soundtrack of the film Heavy Metal.

According to guitarist Tony Iommi's autobiography Iron Man: My Journey Through Heaven & Hell with Black Sabbath, the band began writing and rehearsing songs for Mob Rules at a rented house in Toluca Lake in Los Angeles.

Mob Rules was the first Sabbath album to feature Vinny Appice on drums, who had replaced original member Bill Ward in the middle of the Heaven and Hell tour.

[5] Asked by Joe Matera in 2007 if working with a new drummer was jarring after so many years, bassist and lyricist Geezer Butler replied, "No, because Vinny was a big fan of the band and loved Bill's playing.

In an interview for the concert film Neon Nights: 30 Years of Heaven and Hell, Butler cites "The Sign of the Southern Cross" as his favourite Mob Rules track because "it gave me a chance to experiment with some bass effects".

Vinny Appice stated in a 2021 interview with Pariah Burke that the writing for the album was largely a collaborative process done through jam sessions.

The major problem, noted by Mick Wall in his book Black Sabbath: Symptom of the Universe, was that the balance of power within the band had shifted: "With Bill and Ozzy happy to leave the heavy lifting to Tony and Geezer, in terms of songwriting, coming into the studio only when they were called, even as their flair deserted them over the final, dismal Ozzy-era albums, at least everybody knew where they stood.

Essentially Mob Rules is a magnificent record, with the only serious problem being the sequencing of the material which mirrors Heaven and Hell's almost to a tee."

While the title track was the only song from this album regularly played by Black Sabbath on subsequent tours, "Falling Off the Edge of the World" was performed live by Heaven & Hell (which consisted of the same Black Sabbath lineup that recorded Mob Rules), and "Sign of the Southern Cross" occasionally played live by Dio.

Profiling the album in 2008, Bryan Reesman noted: "Even with Dio bringing in more fantasy-based lyrics and moving the group away from seemingly Satanic verses, the title track to Mob Rules, not to mention its menacing cover could easily imply a call to anarchy.

"[citation needed] In modern re-evaluations, the album is generally looked upon very favorably, with Rolling Stone awarding the album a positive review of 3 stars, and other reviewers such as Allmusic's Fred Thomas observing that "Mob Rules and Heaven and Hell work well as each other's companion pieces, making the first round of Dio-fronted Sabbath material a bright spot surrounded by relatively grim efforts on either side.