Derek and Julia Parker are leading figures in the world of astrology. Since writing their first book together in 1971, the ground-breaking Complete Astrologer, the Parkers have published well over 40 books together. Their best-selling guide Parker's Astrology, first published by DK in 1991 and substantially enlarged and updated in 2001, is generally regarded as the world's best introduction to astrology, selling nearly a million copies in the last five years alone.