Schools, communities, and advocates across the nation have successfully taken steps to ensure children are attending school more regularly. What works is to take a data-driven, comprehensive approach that begins with engaging students and families as well as preventing absences from adding up before students fall behind academically. The key is using chronic absence data as a diagnostic tool to identify where prevention and early intervention are needed. With this data in hand, schools, families and community partners can together determine the causes of chronic absence, and implement approaches that address barriers to getting to class. Attendance Works has developed a set of key strategies for reducing chronic absence in school sites and key ingredients for systemic change that need to exist across a school district and broader communities. Both levels are essential to having a sustained impact. Reducing chronic absence fits nicely into the three-tiered support systems used in many school districts and states.