The Upper Jurassic Kimmeridge Clay Formation of the UK is spectacularly exposed in the sea cliffs of its type locality in south Dorset. It is also seen intermittently through Wiltshire, the home counties, Norfolk, Lincolnshire and in Yorkshire. In Scotland, coeval deposits are seen on both the east coast and on the Isle of Skye. The Kimmeridge Clay is highly fossiliferous, and the preservation of its fossils is often exceptional. It is common to find ammonites with beautiful iridescence and vertebrates in an articulated condition, with stomach contents. This comprehensive field guide, presented in two volumes, reviews all of the major groups, from microfossils to gigantic dinosaurs and pliosaurs. Volume 1 explores the invertebrates, plants and trace fossils, as well giving a thorough introduction to the sedimentology and collecting from the formation. Volume 2 is dedicated to vertebrate palaeontology.