The album was released on April 2, 1990 in Canada and worldwide in September 1990.
The recording took place in Los Angeles, London and New York and lasted almost one year.
Unison is a new version of a song which first had been recorded as theme song in the movie All The Right Moves with Tom Cruise. The original version, recorded by Junior, can be found on the sound track from the movie.
Céline sang Have a heart for the first time at the Juno Awards on November 2, 1987. The song, especially for the event, is an adaptation from the song Partout je te vois which can be found on the album Incognito. Then the song Have a heart had been recorded in studio for the album Unison.