A study attempted to improve the results of correlating personality characteristics with teaching behavior within the setting of a microteaching laboratory. Self-theory constructs were used to predict teaching behavior. Subjects (80 education students) were administered the Self-Report Inventory (SRI) and the Adjective Rating Scale for Self Description (ASD) from which 10 personality characteristics were selected as independent variables. Criteria of four specific teaching tasks (clarifying objectives, assessing readiness, motivating interest, and evaluating outcomes) and two measures of teacher-pupil interaction (using Flander's interaction analysis) were used in analyzing audio tapes of each student's six to nine microteaching lessons in which he was instructed to attend cumulatively to the four teaching tasks. Pearson's product movement coefficients of correlation were computed as an attempt to determine what relationship existed between 1) performance in the teaching laboratory and changes in performance (from first two to last two lessons) and 2) scores obtained on the SRI and the ASD. Personality variables were not found to be significantly related to laboratory performance. Highly significant changes which occurred on all criteria from early semester to late semester were not related to SRI and ASD variables. Interrelationships of the criteria and kinds of change were also studied. Results indicated that other predictive variables of teaching performance should be sought. (JS)