Whip spiders or Amblypygi are very fascinating creatures with their size, their long, yet strong legs and heavily armed pedipalps that make these animals look so terrible to some people. Where they occur, many of the local people are afraid of them and consider them to be poisonous and dangerous. However, they are not poisonous, and they are dangerous only to arthropods and small vertebrates such as lizards and frogs, but not to humans. This is a comprehensive work on all that is known on the biology of these fascinating creatures. Whip spiders (Amblypygi) can be large and terrifying animals with strong, raptorial pedipalps and long antenniform first legs that can produce a span of as much as 60 cm. Others are small and scarcely span 5 cm. They all lead a secretive nocturnal life and are extremely dangerous to other arthropods and small vertebrates. In contrast to spiders and scorpions, they are of no commercial, economic or medical importance and they are difficult to study in the field because of their nocturnal habits, possible reasons why they have been greatly neglected until recently, by scientists and naturalists. Whip spiders represent an old group that dates back to the Carboniferous period. Their partly primitive and partly derived morphological characters and habits make the study of these animals interesting, while observation of their behaviour greatly increases our knowledge and understanding of arachnids in general. The author has studied whip spiders for over 30 years and has revealed an unexpected diversity in a small group consisting of only about 120 species. In the book the author describes their morphology and systematics, their life history, their fascinating sensory biology, their complex mating dances and reproductive biology, and their ecology and distribution. Thus he has made a significant contribution to a better understanding of the of the morphology and biology of the Arachnida as a whole. Whip Spiders is an outstanding contribution to science and it will be of interest for anyone with an interest in Arachnida and for those keeping and breeding spiders. 302 figures.