ABSTRACT The aim of the project is to write the first Etymological Lexicon of the Khmer (Cambodian) language. It will be a linguistically oriented work making use of the latest advances in historical linguistic studies of the Mon-Khmer language family. The Lexicon will present all Khmer words for which cognates can be found elsewhere in the Mon-Khmer family, to list these cognates and distinguish them from borrowings, and to indicate the linguistic arguments which support these claims. Each entry will contain: the meaning of the Khmer word, with culturally and historically relevant comments; a reconstruc- tion of the Proto-Khmeric form; the form found in Angkorian inscriptions; the Khmer script form; the pronunciation; several Khmer dialect forms; a list of Mon-Khmer cognates classed by branch; a list of borrowings from Khmer, especially into the unrelated Thai and Cham languages, but also into related lang- uages; and notes discussing the relevant historical questions. One purpose of the Lexicon is to place the language of theAngkor civilization, and its profound influence on mainland Southeast Asia, in the proper historical perspective, as a medieval transition between prehistoric Mon-Khmer times and the modern Cambodian period.