A series of experiments explored the feasibility of substituting listening for reading requirements in Army training and jobs, with special reference to marginally literate, AFQT Mental Category IV men. Results of these experiments and related earlier research are summarized. Major findings indicate that high and low aptitude men may learn certain materials as well by listening as by reading; some poorer readers prefer to learn by listening rather than by reading. Characteristics of the recorded message that were found to affect listening comprehension include difficulty level of message, linguistic features of speech, and rate of speech. Extensive studies of the use of time-compressed and expanded recordings are described. (Author)