Minute to small (6–30 mm wingspan) moths, often with brightly marked wings. No morphological characters unequivocally define this family. Adults of some species rest with the head held close to the ground and the abdomen lifted; others sit with the body parallel to the substrate. Larvae have diverse habits, and the family includes communal web makers, needleminers, and leafminers.

The family Yponomeutidae, as currently defined, contains almost 600 species occurring in all faunal regions. Eighty-two species are known from North America; 14 species have been reported from AB, and a few others may be found here as well. Various workers have included the Ypsolophidae and Plutellidae in and/or have excluded the Argyresthiinae from the Yponomeutidae. As recognized by Dugdale et al. (1999), this family includes two main lineages, the ermine moths (subfamily Yponomeutinae) and the needleminer moths (subfamily Argyresthiinae). The family is in need of higher-level work, as well as species-level work. Useful publications include Busck (1907), Braun (1940), and Freeman (1960, 1972).