"Knock Three Times" is a popular song credited to Tony Orlando and Dawn. The actual singers were Tony Orlando, Toni Wine, and Linda November, prior to the creation of "Dawn" with Telma Hopkins and Joyce Vincent Wilson. The song was released as a single in November 1970, paired with Orlando's other hit song, "Candida" (also written by Toni Wine). The single hit number one on the Billboard Hot 100 in January 1971 and eventually sold six million copies, also claiming the number-one spot on the UK Singles Chart. The song registered well at Adult Contemporary stations, reaching #2 on Billboard's "Easy Listening" survey.

The composers of this song, L. Russell Brown and Irwin Levine, were thinking of the song Up on the Roof and they wanted to write a song with that kind of lyrical flavor, about tenement living. In the song, the singer has fallen in love with a woman who lives in the apartment directly below him but has no clue as to her interest, so he asks her to respond by either knocking three times on the ceiling (yes) or banging twice on the pipe (no), and the chorus includes sound effects of the two choices. (However, the song never states her response.)

Michael Anthony Orlando Cassavitis was, at the time of the recording, working as a producer/singer for a rival record label, and first heard the tune recorded by another artist and immediately knew the song could be a hit if produced as he envisioned. Cassavitis cut the track under the name "Tony Orlando", having to do the studio sessions on the "down low" to ensure that his current record label wouldn't become aware. Upon release, the song, produced as Orlando had envisioned became a great success.

Knock Three Times actually sold more than 100,000 records a day in New York City alone for ten straight days. The song appears in several motion pictures including Now and Then.

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