This is the third in the FAO series of worldwide annotated and illustrated catalogues of major groups of organisms that enter marine fisheries. It covers the family Polynemidae (threadfins), including 41 species belonging to 8 genera, which is important in commercial and sport fisheries of tropical and subtropical seas, especially in the Middle and Near East, South Asia, Southeast Asia, Oceania and West Africa. It includes a review of habitat and fisheries of the family; a glossary of technical terms; an illustrated key to each genus and all species; and a detailed account for all species, including an illustration of each species, scientific and vernacular names, and information on habitat, biology, fisheries, size, relevant literature and distribution.