Updating the important work done by Osborne and Comaromi in previous editions, this new edition of Dewey Decimal Classification, 20th Edition: A Study Manual (Libraries Unlimited, 1991) introduces readers to DDC21 from a practical user's point of view. After a historical review of the Classification, Scott describes and illustrates the notable changes that have been made to the twenty-first edition. The book provides an in-depth review of how DDC is updated and gives detailed lists of such changes in each table and class. Examples and exercises assist the user in fully understanding the Classification's use, down to the book number. In addition, changes that appear in the 21st Dewey and brief descriptions of their application are included to guide users in applying the Classification in the cataloging process. An extensive bibliography and index complete the work. The most thorough introduction to the twenty-first edition of DDC available, it is an essential purchase for technical services departm