[2] After five consecutive albums peaking inside the US top five, Horizon broke this run by only reaching no.

Karen and Richard hired Billy May, who has worked with artists like Frank Sinatra and Nat King Cole, to help orchestrate the song.

[7] At the time of the release of Horizon, lyricist John Bettis claimed "(I'm Caught Between) Goodbye, and I Love You" to be his and Richard's best collaboration.

[8] Rolling Stone reviewer Stephen Holden acclaimed Horizon, calling it "the Carpenters' most musically sophisticated album to date" and noting that "while not an emotionally compelling singer, Karen Carpenter has developed into a fine vocal technician, whose mellow interpretations of the Eagles' "Desperado" and Neil Sedaka's "Solitaire" evidence professionalism on a par with such Fifties stars as Jo Stafford and Rosemary Clooney.

Against the carefully structured sound of the Carpenter formula, wherein Karen's solos burst in and out of diaphanous multiharmonies, Richard has imposed more elaborately orchestrated textures than before and wisely mixed them at a level that doesn't distract attention from Karen's intimately mixed singing.

Karen's strong and positive voice melds into her lyrics, be they on a now well-known work ("Please Mister Postman" and "Only Yesterday ") or an old evergreen like "I Can Dream Can't I."

Karen's soft qualities plus her blending with brother Richard into an omnidirectional attack provide easy to listen to the material.

"[12] In their review, Cashbox praised the album, stating that "the natural vocals of Karen and the arranging genius of Richard have combined to make the Carpenters' sound a classic in the easy listening market.

Although the sorrow-or-bust ethos of this might put some off, Horizon gains its strength from strong production values and Karen Carpenter's singular gifts as an interpreter.

[15] Although percussion is audible on some of the songs, notably "Only Yesterday", it is not specified who the percussionist is, but this would change with the experimental album Passage, released in 1977.