A study hypothesized that significant relationships exist between personality traits and success in student teaching, and will be manifest between those students demonstrating definitive levels of personality trait characteristics identified as being related to success, and those who do not. The Myers-Briggs Type Indicator (MBTI) was administered 6 weeks into the student teaching experience. The four scales available from data produced by the instrument included scores on a continuum for extraversion-introversion, sensation-intuition, thinking-feeling, and judgment-perception. Success in student teaching was identified by the cooperating teacher's evaluation of the student teacher. The four continuous scores from the MBTI were compared for strength of relationship to success in student teaching at the elementary and secondary levels. Analysis of the data indicated that personality trait characteristics correlated significantly with student teaching success. Of the four scores available from the MBTI, judgment was related to secondary school student teaching success, while sensing and judgment related to success at the elementary level. At the secondary level, the extraversion trait indicated a trend toward a positive relationship to success, and the introversion trait indicated a positive relationship at the elementary level. (JD)