The languages are spoken in the northern Mexican states of Sonora, Chihuahua, Coahuila and to a much lesser degree in Durango and Nuevo León.

The seven Southern Athabaskan languages can be divided into two groups according to the classification of Harry Hoijer: (I) Plains and (II) Southwestern.

Hoijer's classification is based primarily on the differences of the pronunciation of the initial consonant of noun and verb stems.

Mescalero, Jicarilla, and Western Apache are considered endangered as well, with some children still learning the languages despite the number of child speakers continuing to diminish.

To revitalize the languages, the institute created a community based Language Planning Council with native speakers to establish and develop grammar rules and the normalization of the writing system, an official alphabet has been validated since then while other grammar topics are still in development.

Southern Athabaskan languages generally have a consonant inventory similar to the set of 33 consonants below (based mostly on Western Apache): The practical orthography corresponds to the pronunciation of the Southern Athabaskan languages fairly well (as opposed to the writing systems of English or Vietnamese).

Recently, de Reuse (2006) has found that Western Apache also has a mid tone, which he indicates with a macron diacritic ¯, as in ō, ǭ.

Here are some vowel contrasts involving nasalization, tone, and length from Chiricahua Apache: The Southern Athabascan branch was defined by Harry Hoijer primarily according to its merger of stem-initial consonants of the Proto-Athabascan series *k̯ and *c into *c (in addition to the widespread merger of *č and *čʷ into *č also found in many Northern Athabascan languages).

Morris Opler (1975) has suggested that Hoijer's original formulation that Jicarilla and Lipan in an Eastern branch was more in agreement with the cultural similarities between both and their differences from the other Western Apachean groups.

Other linguists, particularly Michael Krauss (1973), have noted that a classification based only on the initial consonants of noun and verb stems is arbitrary and when other sound correspondences are considered the relationships between the languages appear to be more complex.