AbstractCriteria are proposed for defining and selecting preschool developmental screening instruments. These criteria include the purpose, breadth, and psychometric properties of screening tests. The Early Screening Inventory (ESI) is a developmental screening instrument designed to satisfy these criteria. The test samples developmental, rather than school achievement, abilities and focuses on performance in a wide range of developmental areas. The results of several reliability and validity studies performed on the ESI are presented, demonstrating that the ESI predicts school performance with moderate to excellent accuracy through the end of second grade. The usefulness and limitations of the ESI in predicting school performance from kindergarten to grade four are discussed.