"Fear (Of the Unknown)" is a U.S.-only single by written and recorded by English rock band Siouxsie and the Banshees and produced by Stephen Hague. It was released in late 1991 as the third U.S. single from the band's 10th studio album, Superstition. It was not released in the UK and was the only Siouxsie and the Banshees single not to be issued in that country.
The track, in its original form, was an uptempo dance-oriented number with heavy percussion work by Banshees drummer Budgie. For its release as a single, "Fear (of the Unknown)" was drastically remixed by Junior Vasquez to accentuate its 4/4 rhythm and give it a house music feel. When included on the 1992 compilation album Twice Upon a Time: The Singles, the track was presented in still another version, which was neither the main single version (which is the same as the version on Superstition) nor the Junior Vasquez "Vertigo Mix," which was the fourth track on the single.