An outline is presented for a digital computer simulation model for an information network for the State of California. The methodology of simulation is discussed initially. The problems presented by the very large size of the system, in terms of materials, users, communication connections are depicted, and solutions are suggested which permit more efficient handling of them. A scheme is discussed for representing the human element in this essentially man-machine system. Methods are discussed for representing the effects of file organization, both for machine-readable data and for conventional materials of the libraries. (Author)