The phonology of Navajo is intimately connected to its morphology. For example, the entire range of contrastive consonants is found only at the beginning of word stems. In stem-final position and in prefixes, the number of contrasts is drastically reduced. Similarly, vowel contrasts (including their prosodic combinatory possibilities) found outside of the stem are significantly neutralized.
Like most Athabascan languages, Navajo is coronal heavy, having many phonological contrasts at coronal places of articulation and less at other places. Also typical of the family, Navajo has a limited number of labial sounds, both in terms of its phonemic inventory and in their occurrence in actual lexical items and displays of consonant harmony.