The Book of the Nine Judges is a famous medieval compendium of traditional horary astrology compiled from Abu Mashar Mashaallah Sahl bin Bishr Umar al-Tabari al-Kindi Abu Ali al-Khayyat Dorotheus Aristotle and Jirjis. It is the largest known compendium of these sources on answering horary questions and in many cases is the first modern translation of these Latin/Arabic authors. Complete with an introduction to questions by the translator with numerous diagrams tables and an extensive glossary it is essential for traditional astrologers.