Whether by consulting the position of the planets, casting horoscopes or interpreting dreams, the art of divination was widely practised throughout the Islamic world. The most splendid tools ever devised to foretell the future were illustrated texts known as the "Falnama" ("Book of Omens"). Notable for their monumental size, brilliantly painted compositions and unusual subject matter, the manuscripts, created in Safavid Iran and Ottoman Turkey in the 16th and early 17th centuries, are the centre piece of "Falnama: The Book of Omens". This is the first book ever devoted to these extraordinary manuscripts, which remain largely unpublished, and sheds new light on their artistic, cultural and religious significance.