'So Hard' was the first single released from 'Behaviour' and was released before the album. It was highly remixed and released in various formats. For the standard single releases, the original mixdown done by the band and Harold Faltermeyer was extended and remixed. Techno tweekers the KLF were brought on to do a remix as well, and one of the b-side, 'It Must Be Obvious' and those two tracks were released on limited edition record and CD. Rarer even than these are the remixes done by David Morales which were released only on German and US releases and promos.