"Glad to Be Unhappy" is a popular song composed by Richard Rodgers, with lyrics by Lorenz Hart. It was introduced in their 1936 musical On Your Toes by Doris Carson and David Morris, although it was not popular at the time, as there was only one 1936 recording of the tune. In the 1937 London production, it was sung by Gina Malo and Eddie Pola. The song was performed in the 1954 Broadway revival by Kay Coulter and Joshua Shelley.

Originally recorded for their appearance on Rodgers and Hart Today, an episode of ABC Stage 67, the song was released as a single at the end of 1967, reaching #26 on the Billboard Hot 100 chart. It was issued in an effort to keep the group in the charts, while awaiting the completion of what would be their fourth album, The Papas & The Mamas. The song does not appear on that album: it is instead used to promote the group's second Greatest Hits package, entitled Golden Era, Volume 2. It is the last of the Mamas & the Papas singles produced in a professional studio, as subsequent singles were made in the studio constructed within John and Michelle Phillip's home at the time, once owned by actress Jeanette MacDonald. The mono single differs slightly from the stereo album mix - as was common for the group's singles - in that the Papas sing a few additional words during the first chorus in the stereo mix.

The B-side of the single is "Hey Girl", an album track from the group's first lp.

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