The Old World flycatchers are a large family, the Muscicapidae, of small passerine birds restricted to the Old World, with the exception of several vagrants and two species, bluethroat and northern wheatear, found also in North America. These are mainly small arboreal insectivores, many of which, as the name implies, take their prey on the wing. The family is relatively large and includes 351 species which are divided into 54 genera.

A passerine is any bird of the order Passeriformes which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their toes, which facilitates perching.