Blondie members Debbie Harry and Chris Stein (who were a couple) wrote the first version of this song in early 1974, shortly after they first met. They didn't have a proper title for the song, and would refer to it as "The Disco Song." Harry explained on the show Words and Music: "Lyrically, it was about a stalker who was pursuing me, and Chris saved me from him."It wasn't until they recorded this song in 1978 that Stein came up with the title "Heart Of Glass." He didn't know that it was also the title of a 1976 German movie directed by Werner Herzog.
According to Rolling Stone magazine's Top 500 Songs, Harry and Stein wrote the song in their dingy New York apartment and keyboardist Jimmy Destri provided the synthesizer hook. The result brought punk and disco together on the dance floor. Said Destri, "Chris always wanted to do disco. We used to do 'Heart Of Glass' to upset people."
Debbie Harry (from 1000 UK #1 Hits by Jon Kutner and Spencer Leigh): "When we did Heart Of Glass it wasn't too cool in our social set to play disco. But we did it because we wanted to be uncool. It was based around a Roland Rhythm Machine and the backing took over 10 hours to get down."
Chris Stein added, "We didn't expect the original to be that big. We only did it as a novelty item to put more diversity into the album."
Blondie re-recorded this in 1978 in a reggae style, but their producer Mike Chapman suggested reggae didn't sell in America. As Harry and Stein had a fascination with the disco sound that was then sweeping the country, so they adopted a sound that was an amalgamation of their New Wave background and Eurodisco.