The hypothesis that teacher personality characteristics affect student achievement is examined. This paper presents a preliminary analysis of the relationship of teachers' selfdescriptions to their students' changes over a school year. Two types of teacher measurement were obtained: observations of behavior and self reports. All student measurements used were selfreport measures, with the exception of an achievement test. The teacher with whom each child was paired was the sixthgrade homeroom teacher since two to three hours a day were spent with this teacher. During the school year tests were given to the pupils over several class periods at the beginning of the fall semester and near the close of the spring semester. Both teachers and pupils were asked to rate themselves on such personality characteristics as selfesteem, introversion, and reactions to other people. Teachers also rated themselves on such attitudes and coping items as anxiety, authority, handling children in the classroom, task achievement, and positive and negative feelings. The results of a year's observation and comparisons between attitudes and outcomes indicated a modest degree of relatedness between teacher personality and observed teaching behavior. Significant relationships were found between teacher personality and changes in pupils' achievement, attitudes, and selfesteem. (JD)