"If You Were Here Tonight" is Alexander O'Neal's first successful hit in the United Kingdom, reaching #13 in the UK Singles Chart in March 1986 after originally peaking at #81 in August 1985 and also his second R&B hit, reaching #17 in the Hot R&B/Hip-Hop Songs chart. It is featured on his self-titled debut album along with two other R&B hits, "Innocent" and "What's Missing". The song is known for its non-rhyming lyrics.
The song's instrumental was sampled as the basis for the highly popular dancehall beat called the Sail Away Riddim in 1998. This was done by producing an uptempo dancehall beat woven around the airy keyboard riff from "If You Were Here Tonight". The Sail Away riddim was used to produce a 12-track "one-rhythm" album of songs using the same instrumental. Artists featured on the Sail Away album included Beenie Man, Mr. Vegas, Chico, Frisco Kid, Sean Paul, Richie Stephens, T.O.K., Nitty Kutchie, Round Head, Tony Curtis, Copper Cat, and Demo Delgado.
Jamaican reggae singer Wayne Wonder covered the song in 1990, retitled "If You Were Here", taken from his self-titled debut album released the same year.
English singer Matt Goss, formerly of the band Bros, released his version as a single in 1996.