Who produced the 1991 Metallica album Metallica alongside Bob Rock?

James Hetfield and Lars Ulrich produced the 1991 Metallica album Metallica alongside Bob Rock.

Bob Rock received the main producer credit, while Metallica's core creative leaders Hetfield and Ulrich were credited as assistant producers. Their involvement reflected the band's close control over songwriting, performances, arrangements, and the overall recording process.

At the time, Hetfield was the band's rhythm guitarist, vocalist, and principal lyricist, while Ulrich was the drummer. The pair wrote most of the material together, often developing ideas at Ulrich's home in Berkeley, California. Their partnership had shaped Metallica's previous records and remained central to The Black Album.

This credit is easy to mix up with the band's full performing lineup. Kirk Hammett played lead guitar and Jason Newsted played bass, but neither is listed as an assistant producer on the album. Bob Rock's principal producer credit also does not mean he wrote the songs.