Traditional community antenna TV (CATV) systems are designed for program distribution and, as a result, adopt the "tree" network structure. However, this system is not satisfactory in urban environments. There are three solutions to this "lost channel" problem: (1) dual-cable systems; (2) channel converters; and (3) switched CATV systems. In addition, the new Federal Communication Commission (FCC) CATV report and order states that two-way capability will be required in all systems in the top 100 markets by 1977. This service will be capable of remote TV origination, but will not have the channel capacity for private, two-way video conversations in the telephone sense. However, data transmission and services (polling, meter reading, conference call hookups, frame-grabbing, etc.) will be extensive. Two-way services will emerge over the next few years, but their rate of growth is extremely hard to predict at this time. The cable system in a university can be organized like those to subscribers homes; Case-Western-Reserve and Massachusetts Institute of Technology are already experimenting in this area. (WCM)