"Spirits (Having Flown)" is a song by the Bee Gees which was originally released on the 1979 album Spirits Having Flown. Though not issued as a single in conjunction with the parent album, it was released in the UK to promote the compilation Bee Gees Greatest, which was released in December 1979. Its B-side was a 1975 song "Wind of Change" from the group's Main Course.

The song itself is a Caribbean flavored R&B track sung by Barry in natural voice during the verses and joined by Robin and Maurice on the chorus which is sung in falsetto. The count-in (1,2,3,4) heard on the album version was omitted from the single version and on the album Bee Gees Greatest. Flute work for the track was provided by Herbie Mann.

The single peaked at no.16 in the UK, and would be the last Top 40 hit the band had in the UK for almost eight years.

...
Wikipedia