IT IS HELD THAT ALTHOUGH PRESENT TUTORING TECHNIQUES IN LIPREADING FREQUENTLY ACHIEVE REMARKABLE RESULTS, THEY MIGHT BE BETTER UNDERSTOOD AND MADE MORE EFFECTIVE BY THE SYSTEMATIC APPLICATION OF LINGUISTIC CONCEPTS AND METHODS TO THE PROBLEMS INVOLVED. THE INVESTIGATION HAS BEEN CONCENTRATED ON A STUDY OF THE VISUAL PERCEPTIBILITY OF ENGLISH SPEECH, MORE SPECIFICALLY, IT HAS BEEN DEVOTED TO A SEARCH FOR THE LINGUISTIC DETERMINANTS OF PERCEPTION IN ORAL VISUAL COMMUNICATION. THE EXPERIMENTAL APPROACH HAS BEEN TO PROCEED FROM THE DESCRIPTIVE UNITS OF STRUCTURAL LINGUISTICS, AND TO TEST THE PERCEPTION OF THESE UNITS BY EVOKING RESPONSES TO STIMULI APPROPRIATE TO A SPECIFIC LEVEL OF STRUCTURE IN THE SOURCE LANGUAGE. THE RESULTS OF THE INVESTIGATION HAVE YIELDED DATA WHICH ARE FELT TO BE OF POSSIBLE USE IN EDUCATION OF THE DEAF. A REFERENCE MANUAL IS PROPOSED WHICH OUTLINES CRITERIA FOR A SYSTEMATIC CLASSIFICATION OF ENGLISH MONOSYLLABIC WORDS ACCORDING TO A SCALE OF VISUAL COMPREHENSIBILITY WITH THE END OF PUBLISHING A PRACTICAL REFERENCE VOCABULARY FOR USE BY TEACHERS AND STUDENTS OF LIPREADING.