Coeur d'Alene, also known as Snchitsu'umshtsn, is a Southern Interior (Idaho, USA) Salish language. This work presents a formal account of the basic clause structure of this polysynthetic language within the tradition of Minimalism and Distributed Morphology. The work arrives at an account of the basic clause structure and an articulation of the left periphery of Coeur d'Alene. In addition, an account of lexical affixation is presented. Thus providing the first formal account of the language and adding to our understanding of Coeur d'Alene, Salish languages, and languages of the world more generally. In addition, the work draws attention to the excellent scholarship of Gladys Reichard, whose work has been crucial in any study of the Coeur d'Alene language in the last ninety years. Using Reichard's unpublished manuscripts and field notes, as well as consultation with the Coeur d'Alene Language Program, the work draws on a corpus of data that demonstrates the value of legacy material and illustrates the importance of language documentation, maintenance, and preservation to linguistic inquiry.