 Paipai belongs to the Yuman language family.Within the Yuman family, Paipai belongs to the Pai branch, which also includes the Upland Yuman language, dialects of which are spoken by the Yavapai, Walapai, and Havasupai of western Arizona.The relationship between Paipai and Upland Yuman is very close; some observers have suggested that Paipai and Yavapai are mutually intelligible (i.e., that the Paipai and Upland Yumans spoke dialects of a single language), while other observers have claimed that they are not.