This guide addresses the positive and negative issues associated with adapting telefacsimile technology to meet library service needs, and provides basic information about the technology while demonstrating how librarians have begun to incorporate it into their work processes. Individual sections cover: (1) the history of facsimile technologies in and outside of libraries; (2) technological changes and improvements since 1981; (3) specific applications in libraries--i.e., for interlibrary loan, for branch communication, for referral of reference questions, or as a document delivery device; (4) the relationship between electronic mail and telefacsimile; (5) what to look for when purchasing telefacsimile equipment; (6) definitions of 10 key features--e.g., automatic stepdown; (7) maintenance agreements; (8) telecommunications costs; and (9) the future of telefacsimiles. Three appendixes provide definitions of terms not defined in the text; a list of facsimile manufacturers and their telephone numbers; and suggested guidelines for using telefacsimile as an interlibrary loan delivery device. (6 references) (SD)