This paper investigates the concurrent validity of the Teacher Form of the Temperament Assessment Battery. This questionnaire was designed to measure activity level, adaptability, approach/withdrawal, emotional intensity, distractibility, and persistence in children 3 to 7 years of age. In study 1, significant correlations were obtained between several temperament dimensions and observed classroom behavior among first-grade children. Study 2 focused on the relationships between teacher attitudes (attachment, indifference, concern, rejection) and temperament variables. Children nominated for three of the four attitude groups were found to be differentiated from their nonnominated peers by temperament ratings. Finally, correlations between achievement and temperament variables were obtained in study 3.