The purpose of this book is to give a comprehensive review of the facts and trends in veterinary and human parasitology, through contributions from distinguished specialists in different fields. The third edition of the Encyclopedia of Parasitology contributes to these goals in several ways: the number of entries has been increased by about 30, the content has been even more improved by adding more tables and figures. The extensive linking between definitions and essays facilitates information within a minimum of time. More than 40 international contributors, who are well known specialists in their fields, give a comprehensive review of all parasites and therapeutic strategies in veterinarian and human parasitology. Keywords of note: life cycle, parasites, parasitic diseases, chemotherapy, drug action, insecticides, morphology, reproduction, vaccination, vectors.