This review of the evolution of programmed instruction from Pressey and Skinner to the present suggests that current computer technology will be able to free the learner from the limitations of time and place as Pressey originally proposed. It is noted that Skinner provided the necessary foundation for treating the learning process on an individual basis, while Pressey not only provided the necessary technological implement--the teaching machine--but also anticipated the present cognitive perspective and its importance for the instructional technology of the present and the future, i.e., the computer. It is suggested that programmed instruction, with its basis in cognitive psychology, is better able to handle complexity than other forms of instruction, and recent developments in aptitude-treatment interaction (ATI) research are discussed. Finally, the use of intelligent computer-assisted instruction is considered in the context of the SOPHIE (SOPHisticated Instructional Environment) system, and it is suggested that such systems represent the realization of the type of teaching machine first envisioned by Pressey. (EW)