This study summarizes state-level policies surrounding school readiness assessment. A search was conducted to collect and code school readiness policies to document key components of assessment practices in each state, such as if the assessments were mandated or recommended, timing of assessment, measures used, domains of functioning assessed, and the role of school psychologists in assessment. Results indicated that 44 states (86%) use school readiness assessments state-wide, with 34 states fully implementing and 10 states piloting a school readiness measure. Despite this widespread use, only about half of states included guidance related to how to respond to assessment data or students identified as at-risk in their policy documents. In addition, findings indicate that only four states mentioned involvement of school psychologists or other student support personnel in implementation of these assessments. Implications of this study on early childhood assessment policy and directions for future research are discussed. [This paper was published in "Perspectives on Early Childhood Psychology and Education" v4 n2 p39-66 2019.]