This work is the third of a projected group of six volumes on Empidoidea (Diptera, Brachycera) of Fennoscandia and Denmark, and the first concerning the true Empididae, the dance flies, of the taxonomically difficult genus Empis. In total, 64 species and 11 subgenera are treated, including the faunas of Great Britain and the Netherlands. Each subgenus is briefly characterized, with data on phylogeny, distribution, biology, and number of species. The species are fully described and differential characters are illustrated, including the male genitalia. Data are provided for occurrence and distribution, and epigamic and swarming behaviour are reviewed. The Empididae (Diptera) of Fennoscandia and Denmark will serve not only dipterists, but also taxonomists and museologists. It will also be useful to researchers in ecology, zoogeography, evolutionary biology, agriculture and environmental studies.