THE THESAURUS IS DIVIDED INTO THREE SECTIONS OF TERMS: SUBSTANTIVE, ORGANIZATIONAL, AND GEOGRAPHIC. TERMS ARE LISTED ALPHABETICALLY WITHIN EACH SECTION, AND A FIVE-DIGIT NUMERIC CODE IS ASSIGNED TO EACH TERM FOR NCJRS INTERNAL USE. SUBSTANTIVE TERM SELECTION IS BASED, LARGELY, ON THE VOCABULARY OF THE AUTHORS OF THE DOCUMENTS ENTERING THE NCJRS SYSTEM, ON THE FREQUENCY OF TERM USAGE IN THE LITERATURE, AND ON THE LANGUAGE OF THE USER COMMUNITY. TWO TYPES OF SUBSTANTIVE TERMS ARE LISTED: SUBJECT DESCRIPTORS AND SYNONYMS OR NEAR-SYNONYMS. SUBJECT DESCRIPTORS ARE THE AUTHORITATIVE TERMS THAT ARE ACCEPTED FOR INDEXING AND SEARCHING. SYNONYM ENTRIES APPEAR SOLELY TO PROVIDE AS MANY POINTS OF ENTRY TO THE THESAURUS AS POSSIBLE AND ARE FOLLOWED BY 'USE' REFERENCES WHICH INDICATE A PREFERRED VALID DESCRIPTOR OR CONCEPTUAL RELATIONSHIP OF THE SYNONYM TO A DESCRIPTOR. NARROWER TERM (NT), BROADER TERM (BT), AND RELATED TERM (RT) ENTRIES INDICATE HIERARCHICAL RELATIONSHIPS AMONG TERMS OF THE SAME CLASS. SCOPE NOTES ARE OFTEN USED TO EXPLAIN THE SPECIFIC USE OF A TERM IN THE NCJRS SYSTEM. ORGANIZATIONAL AND GEOGRAPHIC DESCRIPTORS, IN THEIR RESPECTIVE SECTIONS, ARE TREATED IN THE SAME MANNER AS THE SUBSTANTIVE TERMS.