The first edition of this book, published in 1982 by the University of Queensland Press, established itself as the main introductory textbook on marine parasitology. It provided an overview of the types of marine parasites and their hosts, hyperparasitism, adaptations, host-parasite interactions, ecological niches, geographical distribution, as well as economic and medical aspects of marine parasites. The second edition has been reviewed to take account of recent advances and includes an additional chapter on the structure of marine parasite communities. There are also new sections on pollution, translocations of hosts and parasites, and on the effects of parasites on the aquaculture of marine fish, molluscs and crustacea. The chapters covering ecological, zoogeographical and economic aspects have also been significantly changed. Aimed particularly at students and research workers in parasitology, the book will also be of interest to ecologists, biologists concerned with zoogeographical problems, and to fish and fisheries biologists.