This network planning paper discusses creation and maintenance of authority files as one of the essential components of bibliographic control, which is a prerequisite to the access of information. Authority files impose consistency on the organization of information and thereby greatly facilitate information retrieval. In the creation of a union list of materials, these authority files become the normalizers of entries, making it possible for users to obtain maximum holdings information. This paper includes 19 task considerations for the creation of authority and bibliographic files in relation to background data, network configuration, and authority system design. Topics discussed include the library catalog, its functions, basic problems, and cataloging in a network context; the authority file; the national library network resources and participants; a MARC format for the authority file; and guidelines for cataloging and design considerations for the file. (Author/MBR)