Using nationally representative data from the Family and Child Experiences Survey 2009 cohort (n = 2,842), this study examined the implications of 3- and 4-year-old's absences from Head Start for their early academic learning. The findings from this study revealed that children who missed more days of school, and especially those who were chronically absent, demonstrated fewer gains in areas of math and literacy during the preschool year. Moreover, excessive absenteeism was found to detract from the potential benefits of quality preschool education and was especially problematic for the early learning of children who entered the Head Start program with a less developed skill set. Implications for policy and practice are discussed. [For the corresponding grantee submission, see ED578435.]