This chapter shows that the interplay of interdialectal and interlinguistic influences in a complex linguistic situation accounts for very nearly all phonological developments. Salishan is a widely ramified stock of considerable time depth and extensive geographic spread in western North America, where it comes into contact with a number of other distinct stocks. The Salishan languages are found in a series of linguistic islands in the general English-speaking environment. The total number of people speaking Salishan languages has been estimated at about 59,000 in 1780, over half of them in the coastal areas. The bulk of the Salish territory is occupied by the seven languages of the Interior Division. This is in keeping with the general pattern of North American linguistic geography. Salish probably has distant affinities with Wakashan and Chemakuan; an even more remote connection has been suggested by Sapir with Kutenai and Algonkian. Among the phonemic systems of Salish there are several marked differences of detail.