Fourth Dimension was a 1973 library recordings release by BBC Radiophonic Workshop composer Paddy Kingsland. Although it was credited to "The BBC Radiophonic Workshop" it was the work of Kingsland alone, and was the first album of Workshop music to feature only one artist. It features theme tunes that were used by a number of BBC radio and TV stations. The music prominently features VCS 3 and "Delaware" Synthi 100 synthesisers, both from Electronic Music Studios (London) Ltd, with a standard rock-based session band providing backing. The track "Reg" featured as the B-side to the 1973 single release of the Doctor Who theme.