Results of a recent study of potential demand for electronic information transfer services in 1970-1990 are presented. Projections are made for new services such as electronic mail, remote library browsing, checkless society transactions, video telephone and others, as well as conventional services such as telephone, telegraph and network program transmission. The principal method used was one of determining a valid projection parameter specific to each service, using past trends including analogous logistic growth curves to project demand for the services, then combining the requirements into common categories such as voice, video, record and data, and written material. Major conclusions of the study indicate that, while voice will continue to dominate in terms of input to a total (both local and long distance) "U.S. information system," other potential services will also generate large amounts of information transfer. (Author)