State policymakers are increasingly focused on closing the achievement gap and preparing all students to succeed in school and life. However, college and career readiness begins long before students enter high school or even a classroom. Differences in children's abilities appear as early as the first year of life, and research has shown that targeted interventions during the early childhood years can narrow the "school readiness gap." By ensuring that data are accessible and stakeholders have the capacity to use data appropriately, coordinated state early care and education (ECE) data systems will promote data-driven decisionmaking to improve the quality of ECE programs and the workforce, increase access to high-quality ECE programs and, ultimately, improve child outcomes. The 10 ECE Fundamentals outlined here provide the foundation for answering the critical questions that policymakers seek to answer. By taking these steps, states will ensure that stakeholders, from policymakers to parents, have access to the types of information that will allow them to make informed decisions. (Contains 4 footnotes.)