The report provides detailed information about the methods and instruments used to evaluate school readiness initiatives, discusses important considerations in selecting instruments, and provides resources and recommendations that may be helpful to those who are designing and implementing school readiness evaluations. Study results indicate that state and local evaluators have used a variety of instruments to collect child outcome data, some that are well known and others that are not. In general, many of the better-known instruments demonstrate adequate psychometric properties (reliability and validity, which ensure that the instruments consistently measure what they were intended to measure), but a number of issues, such as the appropriateness of the measure to the study's purpose and sample, appear to present substantial challenges in evaluations of state- and locally-funded school readiness programs. Recommendations based on the data collected from this sample are provided to help school readiness programs and evaluators as they select instruments for assessing programs and implementing the evaluations include: (1) Careful selection of outcomes for assessment that match the goals of the program and address the components of children's learning and development that are linked with later success in school; (2) Clear definition of the purpose for which assessment data will be collected, and selection of instruments designed and validated for that purpose; (3) Selection of instruments that have a proven track record; (4) Selection of instruments that are culturally and linguistically appropriate; (5) Consideration of data collection (internal/external); (6) Assessment administration, including training and reliability studies; and (7) Data collection in context. Report findings highlight the challenges that evaluators face in ensuring that data are collected in a manner that yields credible, trustworthy, and meaningful information about child outcomes. The report cites a number of resources that can assist evaluators in making decisions about child assessments: resources to guide decisions about how to assess child outcomes, reviews of measures, and web sites with technical information related to measures used in large federal studies. Four appendixes include: (A) Methodology; (B) Coding Sheet and Evaluations Reviewed; (C) Evaluation Reports Reviewed, by State and Program; and (D) Descriptions of Most Commonly Used Instruments. (Contains 4 boxes, 6 figures, 4 tables, and 28 notes.) [This report was prepared for the Institute of Education Sciences (IES) by Regional Educational Laboratory Southeast administered by SERVE Center, University of North Carolina at Greensboro.]