This volume consists of a classification of the world's languages. The book is organized alphabetically in terms of classes. Within each class, the title of each entry is the name of a group of related languages. On the whole, the groups of languages discussed in an entry represent genetic units or purported genetic units. The internal relationships of the members of the group covered by an entry are discussed in an initial paragraph under the heading "grouping," after which the members of the groups, or the various subgroups within it, are listed. After the discussion of their internal grouping, the languages belonging to the group treated in an entry article are listed. A given language may be identified by a single name or by two or more alternate names. The name of the language (with its alternates) is followed by the names of its dialects, where known, as well as the number of speakers of the language and the location of those speakers, where such information is available. Finally, the relationship of the group as a whole to other groups of languages is given under the heading of "affiliation." A reference list and an index of dialects, languages, and language groups conclude the volume. (Author/CLK)