To test the hypothesis that aspects of one's personality are associated with expansion of his or her vocabulary, a study focused on thirteen students of various ages who constituted a vocabulary development class. Students were taught techniques for discovering meaning through context or extracting meaning through word structure. Considerable time was also spent in dictionary use as well as in a workbook approach to Latin and Greek roots, adverbs, and adjectives. During a 10 week quarter, students took a pretest, weekly quizzes, a midquarter exam, and the final exam containing a posttest. At the end of the quarter, students took the Myers-Briggs Type Indicator derived from Carl Jung's personality typology. The questionnaire classified students according to four major dichotomous groupings, each designed to indicate direction or a "habitual choice betwen opposites": (1) extraversion or introversion, (2) sensing or intuition, (3) thinking or feeling, and (4) judging or perceiving. Responses and test scores indicated that students who were intuitive types consistently did better than students who were sensing personality types. The intuitive-perceiving type even surpassed the intuitive-feeling type. Among the sensing types, those who were sensing-thinking had higher pretest scores than the sensing-feeling students. (HOD)