The family Mephitidae, which includes the skunks and stink badgers, is comprised of four extant genera (Mephitis, Conepatus, Spilogale and Mydaus) and 13 species. While many authors have traditionally considered skunks a subfamily (Mephitinae) within Mustelidae, recent molecular evidence indicates that skunks do not lie within the mustelid group and should be recognized as a single family, Mephitidae, a systematic understanding that is accepted here. Stink badgers (Mydaus) have only recently been considered part of the skunk clade (Dragoo and Honeycutt, 1997; Flynn et al., 2005).

Three of the four genera of skunks inhabit the New World, collectively ranging from Canada to central South America; the exception are stink badgers (Mydaus), which occur on islands in Indonesia and the Philippines. Skunks are distinguishable by their conspicuous patterns of black and white stripes or spots, which serve as aposematic signals to would-be predators. Skunks have extremely well-developed anal scent glands with which they produce noxious odors to deter threats. Spotted skunks (Spilogale) are the smallest members of this family, weighing between 200 g and 1 kg. Hog-nosed skunks (Conepatus) reach the largest sizes (up to 4.5 kg). Mephitids have relatively long rostra (although not so pronounced in Spilogale), broad, squat bodies, and often a thickly-furred tail. They have short limbs and robust claws that are well-suited for digging.

Mephitids are mainly omnivorous. They often eat vegetation, insects and other small invertebrates, and smaller vertebrates such as snakes, birds and rodents. Mephitids are nocturnal, and inhabit a range of habitats that includes woodlands, deserts, grasslands, and rocky montane areas. They typically do not occur in dense forest. Skunks and stink badgers are adept diggers, which allows them to find food in the soil as well as to help excavate their dens. Some species can climb trees, either to seek shelter or to find food.