Defining cognitive style as the modes an individual uses in perceiving, organizing, and labelling aspects of his or her environment, this paper is the first in a series concerning some implications of a learner's cognitive style for the development of reading competence. The paper identifies nine dimensions of cognitive style and then provides a review of the literature suggesting that two of the nine dimensions--field dependence/independence and reflectivity/impulsivity--are significantly related to reading achievement. The paper notes that field dependent children tend to make global responses to phenomena and have been shown to have a lower level of reading achievement than field independent children, who tend to perceive things analytically. It notes that impulsive children have also been shown to have a lower level of reading achievement than reflective children. The paper suggests that cognitive styles of students should be taken into account in relation to materials and the teacher's own cognitive style. It concludes that the primary role of the teacher becomes one of a learning diagnostician and program director with the implication that no one instructional program or no one teaching strategy is appropriate for all children. (MKM)