Composed by Barry, Robin and Maurice Gibb of the Bee Gees. Recorded by Yvonne Elliman for the film Saturday Night Fever. The single was the fourth released from the soundtrack album. It reached No.1 on the Billboard Hot 100 Chart in the USA in May 1978, ending an eight week run at the top of the Chart for Night Fever, also from Saturday Night Fever. The composers later released their own version of the song: www.youtube.com/beegees/ificanthaveyou.