This study evaluated the reliability and validity of a revised teacher rating scale of disruptive behavior with preschool-aged children. The Sutter-Eyberg Student Behavior Inventory-Revised (SESBI-R) was completed by teachers of 74 nonreferred preschoolers and 49 children referred for evaluation of behavior problems, age 3 to 6. Results of the study demonstrated satisfactory internal consistency, testrestest stability, and inter-teacher agreement, as well as the absence of systematic bias in scores over repeated administration. Analyses also showed no differences in SESBI-R scores by children's age, gender, or ethnicity. Evidence of convergent, discriminant, incremental, and discriminative validity was demonstrated, in addition to criterion validity for the factor scores of the SESBI-R. The results of this study suggest that the SESBI-R is a promising instrument for measuring classroom behavior problems in preschoolers.