An important advance in computer assisted instruction (CAI) is the development of authoring systems that allow teachers to write software without the need for direct use of a higher level language. The primary advantage of authoring systems is that they provide teachers with the means to write CAI in plain English rather than using a computer language. Putting lesson contents completely under teacher control, these systems let teachers emphasize specific instructional objectives, give selected materials detailed treatment, or tailor remedial programs to meet the needs of individual students. Another advantage of authoring systems is that they permit modification by teachers at any time. Design features to consider when evaluating authoring systems include their instructional methods, ease of use with all instructional strategies and by all authors, flexibility, and editing and record keeping abilities. Finally, the CAI language design should include statistical programs to sort and perform elementary statistical processing of individual as well as group data. (Included is a listing of some available authoring systems.) (HOD)