This report, which will serve as a foundation for the UChicago Consortium's future studies of the Prairie State Achievement Exam (PSAE), presents key issues related to the exam. The report's author discusses basic facts about the PSAE, such as its origination, its component tests, the subject areas it covers, how it is scored, and how scores are reported. The author then describes how PSAE scores are used in accountability policies. The report contains analysis of student performance on various parts of the exam and relationships between component tests. Performance comparisons across various groups of students are also presented.