The Gesell School Readiness Screening Test (GSRST) is widely used to identify "developmentally immature" children for placement in extra-year, transition programs in spite of a problematic absence of psychometric evidence and research support. In this study of psychometric characteristics of the GSRST, teacher ratings of classroom performance and readiness, selected subtests from the Kaufman Assessment Battery for Children (K-ABC), and parent reports of adaptive behavior were obtained for a sample of 48 kindergarten children. There was a moderately high correlation between the GSRST and K-ABC subtests. There was a high level of agreement between placement recommendations based on GSRST results and teacher ratings of readiness. Test-retest reliability and interrater reliability for the customary clinically-based scoring method were below acceptable levels, and lower than the reliability figures yielded by a quantitatively based scoring method. The GSRST does not appear to be sufficiently reliable for use as a primary determinant of grade placement, but may be a valuable component of a school readiness assessment. The construct of school readiness as measured by the GSRST remains in need of clearer definition. (Author/RH)