Imogen Jennifer Jane Heap ( IM-ə-jən HEEP; born 9 December 1977) is an English musician, singer, songwriter and record producer. Her work has been considered pioneering in pop and electropop music.

Heap classically trained in piano, cello, and clarinet starting at a young age. She began writing songs at the age of 13 and, while attending boarding school, taught herself music production. After being discovered by manager Mickey Modern while attending the BRIT School, Heap signed to independent record label Almo Sounds at the age of 18 and later began working with experimental pop band Acacia. She released her debut album, an alternative rock record, I Megaphone, in 1998. In early 2002, Heap and English record producer Guy Sigsworth formed the electronic duo Frou Frou and released their only album to date, Details (2002).

Her second studio album, Speak for Yourself, was released in 2005 on her own label, Megaphonic Records, and was certified gold in the United States and Canada. The album spawned three singles: "Headlock", which became her first entry on the Billboard Hot 100 20 years after its release; "Goodnight and Go", which became her highest-charting single as a lead artist on the UK Singles Chart; and "Hide and Seek", which was certified gold in the United States and gained popularity after being used in the Fox teen drama television series The O.C.. Heap's third studio album, Ellipse (2009), peaked in the top five of the Billboard 200 chart and received mostly positive reviews. This was followed by her fourth studio album, Sparks (2014). In 2017, she reunited with Sigsworth as part of Frou Frou.

Heap developed the Mi.Mu Gloves, a line of musical gloves, as well as a blockchain-based music-sharing program, Mycelia. She also composed the music for the West End and Broadway play Harry Potter and the Cursed Child. Over the course of her career, she has received two Grammy Awards, one Ivor Novello Award, and one Drama Desk Award. In July 2019, Heap was awarded an honorary doctorate from Berklee College of Music.