The authors put forth various theories and interpretations used by contemporary scholarship to explain their topics and present opposing ideas in an objective way. Given the complex interplay of social, economic, and political influences on every institution over the course of the century, discussions of economics or politics are as common in articles in "The American People" or the "Culture" sections as in the "Politics" or "The Economy" sections. Indeed, subdivision headings within articles often incorporate these terms. Given the scope and length of the essays (spanning 20 to 30 double-columned pages), the subdivisions are helpful in locating discussion of particular aspects of a topic. It would have been helpful if an outline of its contents appeared at the head of each article. Black-and-white maps and tables are provided, and a few entries, especially in volume 4 ("Culture" ), are illustrated with black-and-white photographs. A thorough index in volume four provides access to specific topics. It includes numerous references to personal names, and its broad topical entries are refined through numerous specific subdivisions. This index is also reprinted in a separate paperback volume that includes a chronology. Because the set is in a classified, not an alphabetical, arrangement, use of the index will be necessary.
Each essay concludes with a bibliographic essay that guides readers to additional sources and evaluates the sources drawn on and quoted within the essays themselves. The writers focus on the how and why of societal change. For example, those who today make bold predictions for the ways in which the Internet will change society would do well to read the essay on computer and communications technology; it relates similar past claims, yet to be fulfilled, for the telephone and other technologies. Indeed, anyone who wants to understand how some aspect of American culture or society has come to be what it is today would do well to turn to the appropriate essay in this encyclopedia. In its breadth it makes a unique contribution while it simultaneously complements sources that focus on the what and when of American history. As we approach the millennium, reference publishers are issuing works that attempt to sum up the century. Encyclopedia of the United States in the Twentieth Century succeeds well in doing this for an academic audience.