While shooting for the film, then called Slammer, Madonna had requested Patrick Leonard to develop an uptempo song that captured the nature of her film persona. She later added the lyrics and vocals to the demo tape developed by Leonard, and decided to rename the song as well as the film to "Who's That Girl".
The song became Madonna's sixth single to top the Billboard Hot 100, while peaking atop the charts in countries like the United Kingdom, Canada, Netherlands, Ireland and Belgium.
It was also nominated for "Best Song From A Motion Picture" at the 1988 Grammy Awards and "Best Original Song" at the 1988 Golden Globe Awards.
The music video portrayed a different persona of Madonna, rather than her film character for which it was released.
Madonna has performed the song on her Who's That Girl World Tour (1987) and on the Rebel Heart Tour (2015-2016).