A survey of the language usage patterns in Zaire begins with an overview of usage of French as the official language and Swahili, Lingala, Ciluba, and Kikongo as the four national languages used both in their respective regions and as part of the mixture of languages used for official and unofficial communication purposes. The systematic study of the languages and development of orthographies and some standardized dialects during French colonization, and recent trends in language policy and preservation are outlined. A matrix follows that rates each of these languages on: (1) their usage rating using State Department classifications; (2) increase and decrease trends by the year 2000; (3) chief of state use in addressing and populace; (4) use in armed forces; (5) use in government, court, and diplomatic communications, written and oral; (6) use as a language of instruction or required language in higher education, on the secondary and elementary levels, and in adult education; (7) use in the popular press, radio and television broadcasting, and film; (8) business and professional use, written and oral; (9) use in intellectual circles; (10) the alphabet situation; (11) their status in literature; (12) use in public signs and notices; and (12) the availability of instructional materials and dictionaries for use by English speakers. Explanatory notes give the number and population percentage using the languages, the type of alphabets used, and specific instructional material titles. A selected bibliography is also included. (MSE)