The principal objective of this report, the last in a series of three, was to develop and determine cost effectiveness of alternate plans for an effective telecommunications capability through 1975 for the State of Illinois. The State is advised to contract with communications consultants to help it save money on its telephone bill. It is also advised to set up a management organization to integrate its telecommunications facilities. Computerization of portions of the management function is recommended. Nine telecommunication approaches that the State may take are considered; of these, five are costed in detail and are the basis for the development of seven competing telecommunications plans. The highest cost plan is 35 percent higher in cost than the lowest cost system; but cost is not thought to be the only consideration. It is concluded that although the state-owned and leased administrative networks are at least 45 percent more expensive than the common carrier network, they provide greater reliability and survivability. It is recommended that the State should buy more equipment and use the new frequencies, but that no extensive replacement of equipment should be made at this time. Appendices include extracts from legislation setting up telecommunication management organizations. A glossary is given. (MF)