"So Long" is a song by Swedish pop group ABBA, released as the first single from their self-titled album ABBA. "So Long" was written and composed by Björn Ulvaeus and Benny Andersson, with lead vocals by Agnetha Fältskog and Anni-Frid Lyngstad.
Backed with "I've Been Waiting for You", another song from the same album, the single was a hit in some European countries, although failed to chart in the UK, despite TV promotion and relatively favourable reviews in the music press.
ABBA