This paper offers an example of how to apply action research to improve English-as-a-Foreign-Language (EFL)/English-as-a-Second-Language (ESL) writing instruction. This research was conducted over a 5-year period while the researcher taught 9 semester-long sections of advanced EFL writing to Taiwanese undergraduates. Using Reid's (1987) Perceptual Learning Style Preference Questionnaire and the researcher's own open-ended surveys, information was systematically analyzed and gathered about students' learning style preferences. The underlying goal of the study was to understand the relationship between learning styles and EFL/ESL writing, and to subsequently understand the students and better discern what approaches would both accommodate and challenge them. The Myers-Briggs Type Indicator with its four Jungian categories of types (extroversion-introversion, sensing-intuition, thinking-feeling, judging-perceiving) was used. It was found that students were generally hostile to any writing instruction because their primary goal in learning English was to learn to talk to foreigners, not to write to them. It is concluded that teachers should first try to explore systematically the learning style preferences of their students before beginning to teach. (Contains 38 references.) (KFT)