The Jugic (Sym-Keltic) language, along with Ket and some other extinct languages from the 18th and 19th centuries, belongs to the group of isolated Yeniseian languages, which are conventionally classified as Paleo-Siberian languages. Jugic was spoken until the 1970s. Heinrich Werner had the opportunity to work with the last speakers of Jugic and to record their language. The monograph based on these recordings describes all areas of the language in detail and includes Jugic texts that could still be documented in writing.