The System Transformation for Equitable Preschools (STEP Forward with Data) Framework is designed to help preschool leaders use data to promote greater equity at every step of their system. It is intended to help preschool systems leaders understand the experiences of children, families, or workforce members within their systems to begin identifying potential inequities and examine root causes that could be addressed. The Framework was developed by the Early Childhood Data Collaborative at Child Trends, in partnership with a consortium of experts. The intended users of the Framework are preschool system leaders— those who can influence decisions or establish a policy for more than one preschool program or site. The STEP Forward with Data Framework is organized into six preschool system steps that can contribute to inequities that a child, family, or workforce member may face and on which a preschool system leader could make actionable changes to improve quality and access to equitable preschool experiences. Across the six steps, there are 20 essential questions for preschool systems leaders to answer, understand, and address. (author abstract)