Polychaetes comprise the bulk of the diversity of Annelida (segmented worms) and are found in nearly every marine habitat, from intertidal algal mats to the deepest sediments. Since being formally named by Linnaeus in 1758 the number of accepted species level taxa has grown to around 9000, though it is certain that there are many more polychaetes to be described and that their importance in the diversity of marine animals will be increasingly recognised. After an introduction outlining the history of polychaete study, and a summary of the book's taxonomic layout, the authors proceed to discuss the methods of polychaete collection and how best to preserve them. This is followed by an overview of polychaete anatomy (with relevant terminology), and a discussion of polychaete systematics, fossils, and ideas about the phylogeny of the group. The remainder of the text is comprised of 72 taxonomic chapters that provide unprecedented coverage of polychaete diversity. Lavishly illustrated with colour plates, the beauty and variety of polychaetes has nowhere been better shown.