Klallam is the language of the Lower Elwha Klallam, Port Gamble S'Klallam, and Jamestown S'Klallam Tribes. It is spoken on the north shore of Washington's Olympic Peninsula from the Strait of Juan de Fuca inland into the mountains, Vancouver Island's Becher Bay, and other small adjacent islands. An endangered language, Klallam is being revived through the Klallam Language Program.

Together with the comprehensive Klallam Dictionary, this pedagogically oriented reference grammar thoroughly documents the Klallam language, providing a resource to linguistic scholars as well as to the Klallam people that will ensure their language survives. A multi-decade collaboration between linguist Timothy Montler and elders, educators, and tribal councils, the grammar progressively covers all the major grammatical constructions and processes of word formation. The Klallam Grammar significantly enriches our understanding of the Klallam language and culture.