The fourth of four volumes, this report documents the implementation, evolution, and institutionalization of the Individualized Study by Telecommunications (IST) Program, a microcomputer-based system developed by the Educational Telecommunications for Alaska (ETA) Project to provide instruction and a set of core courses for rural high school students in Alaska. Following an overview of the context of educational needs in Alaska and a discussion of educational needs assessment in Alaska prior to ETA is a detailed account of IST development, with particular attention to project design principles, the formalization of the IST Instructional Needs and Implementation Plan (including user needs assessment and instructional alternatives analysis), the IST developmental configuration, the IST courseware development process, field testing of courseware (both exploratory and pilot testing), special courses developed for teaching general mathematics and developmental reading, operational testing, and the institutionalization of IST. Appended to the text are a set of review sheets for use in developing IST courses, cost models for field testing the system, information on the LEARN/Alaska network, and a list of new courses sponsored by the ETA project. A list of abbreviations and a bibliography are also attached. (JL)