Four major books were published on the flea fauna of North America during the 20^th Century. The first of these was on the fleas of the eastern United States by Irving Fox (1940a). The second, dealing with the fleas west of the 100^th meridian in the United States was by C. Andresen Hubbard (1947). The third and fourth concern the Canadian flea fauna and both were written by George P. Holland (1949b and 1985). The latter of these included Greenland and Alaska as well. Many new taxa have been described and many taxonomic changes have occurred since the publication of the older works. The current treatment addresses the fleas of all of North America north of Mexico. A chapter on flea development is followed by a description of the anatomy of adult fleas. The major focus of the volume is the identification of taxa. There are keys to the identification of the ten families, 80 genera, and 316 species of North American fleas. For each species, there are illustrations of the taxonomically important features of both the male and female adults. Host and biogeographic information are given for each species. Extensive lists of the published reports of the species are designed to aid future workers. Appendices address biographies of North American flea workers, lists of new synonymies, and a host list by current scientific name. A taxonomic index is provided for the fleas along with a separate index for the hosts.