During the recording of this album, Moraz was a member of The Moody Blues, while Bruford's band King Crimson had just begun a hiatus that would last for ten years.

Flags features ten original instrumentals, mostly derived from the duo improvising or working with sketches.

"[2] The authors of The Penguin Guide to Jazz Recordings wrote: "There are one or two alarming moments when one might be listening to The Carpenters jamming at home.

Then it's Stravinsky; then..."[4] In an article for Jazz Times, Bill Milkowski called the album "an overproduced studio outing," and wrote: "The album opens on a decidedly sour note with the bombastic, overproduced 'Temples of Joy,' which sounds like the theme to an '80s sitcom.

"[5] Writing for All About Jazz, John Kelman noted that "the chemistry between the two is clearly evident," and commented: "more ambitious than Music for Piano and Drums from a production perspective, Flags is clearly a completely different record, based more on overt structure and through-composition that manages to demonstrate the potential power of the duo.