"This controlled vocabulary comprising approximately 1,030 terms commonly used in the field of international development communication was created by the Clearinghouse on Development Communication of the Academy for Educational Development to analyze and index documents. This standard list of terms, designed to provide subject access to information in this area, was constructed by extracting key concepts from relevant documents. The initial list was revised after testing for precision and recall, and reviews by clearinghouse personnel and other subject experts. Arranged in alphabetical order with cross references, the controlled vocabulary has several features. Terms accepted for indexing and searching are printed in upper case letters and are called descriptors; synonyms appear in lower case letters and are not valid descriptors. Symbols appearing under descriptors are used to direct the searcher to a preferred term, clarify meaning, and indicate relationships of terms. Some proper names of countries and international organizations appear in the thesaurus as identifiers, and 'pubtypes' identify types of documents. It is recommended that the most specific terms available to fit the specificity of the document be assigned, and that the real content of the document be indexed. Procedures for updating the thesaurus and thesauri consulted are included."