The Time-shared Interactive Computer-Controlled Information Television (TICCIT) system represents a considerable technological advance over previous CAI systems, primarily because of its unprecedented foundation in instructional theory. This paper briefly describes the theory-base of the TICCIT system; it summarizes some recent advances in instructional theory for sequencing and synthesizing related parts of a subject matter; and it describes three major implications of those advances for the design of future theory-based CAI systems. Those implications concern (1) the selection of content; (2) the use of strategies for sequencing, synthesizing, and summarizing; and (3) the provision of knowledge necessary for the learner to make good strategy decisions. (Author)