The effect of clarity of explanation on student learning and perception of teacher and course effectiveness is examined. Two levels of clarity were utilized, as determined by appropriate use of examples and sequencing of instruction. Three instruments were used to measure the dependent variables: university student rating form; affective questionnaire; and a twenty-item posttest designed to measure student learning. Three groups of university students participated in the study: experimental (unclear) and experimental (clear), both receiving treatment, rating form, questionnaire, and posttest, and control, receiving only treatment and posttest. Results of the study suggest the relative independence of clarity of explanation from other indicators of teacher effectiveness as judged by students on the teacher rating instrument. Results also confirm that significant learning occurred during the clear presentation. (Author/MJB)