This technical memorandum presents an outline of how to apply psycholinguistic and intellective concepts in order to enhance the readability and comprehensibility of written materials. Guidelines for making the reader's task easier are provided, and some readability measurement procedures are also discussed. The contents include: "Increasing Readability/Comprehensibility," which discusses morphemes, sentence voice problems, negativity problems, self-embedding, depth, complements, and branching; "Helping the Reader's Intelligence to Work Easily," which looks at deemphasizing vocabulary diversity, seeing generalizations, cutting down unnecessary details in figures and diagrams, repeating facts for the reader, organizing the material, and avoiding abbreviations: and "Measuring Readability," which discusses the use test, the comprehension test, rating by experts, the cloze procedure, element counting techniques, and more details on readability measures. (WR)