This paper describes the internal tape library system planned for the TX-2 computer at Lincoln Laboratory, Massachusetts Institute of Technology (MIT). One hundred magnetic tape transports will be under the control of a central electronic system; the system will have a storage capacity of 1010 bits and an access time of about 30 seconds. It is particularly well suited for use with a computer of large random-access storage capacity such as TX-2, which has a core memory of 2 1/2 million bits. A simple tape transport having a high-speed search mode with redundant information transfer will make the ultimate library system for a computer, reliable and relatively in-expensive.