&Miss You in a Heartbeat& is a 1993 song by British hard rock band Def Leppard from their album Retro Active.
Three versions of the power ballad appear on Retro Active; the acoustic version (4:04), which was released as the single, the electric version (4:56), which was one of the bonus tracks for the Japanese pressing of Adrenalize along with &She's Too Tough&, and the piano version which is featured as a hidden track on the Retro Active album. It is played after the electric version of &Two Steps Behind&.
The single peaked at number 39 on the US Billboard Hot 100 and was Def Leppard's last top 40 hit single.
Although guitarist Phil Collen had written &Miss You in a Heartbeat&, it was released first on the self-titled 1991 debut by The Law, a band featuring Paul Rodgers and The Who drummer Kenney Jones.