When students are not in school, they miss the opportunity to grow academically, socially, and emotionally. These skills are critical for continued success in school, in the community, and onward into adulthood. Students with low attendance have been shown to be at heightened risk of high school dropout, as well as other potentially deleterious behavior. For these reasons, the issues of truancy--when students have repeated, unexcused absences--and chronic absenteeism--when students repeatedly miss school for any reason--are receiving increased attention in communities, schools, and with parents. At the request of the Redwood City 2020 Cabinet, the John W. Gardner Center for Youth and Their Communities (JGC) at Stanford University conducted an analysis to study truancy and chronic absenteeism among Redwood City students. Through the Youth Data Archive (YDA)--a JGC initiative that links administrative data on individual youth across settings to collectively examine questions that agencies could not answer alone--researchers linked data from Redwood City School District (RCSD), Sequoia Union High School District (SUHSD), and San Mateo County Human Services Agency (HSA). With these data, researchers examine the extent to which truancy and chronic absenteeism are present in the greater Redwood City area, and to explore the causes, consequences, and correlates of absenteeism that may be present in the community. Findings from this analysis show that kindergarteners had the highest rates of chronic absence in the two school districts, which may point to the need for interventions targeted both at students entering school for the first time and their parents; students who were chronically absent were more likely to repeat their chronically absent behavior in subsequent grades, underscoring the importance of early intervention; and students with excessive absences were found to have lower achievement on both the math and English Language Arts California Standards Test. (Contains 11 exhibits and 4 footnotes.) [This research was funded by the Redwood City 2020.].