Early reading development is a complex process that includes the acquisition of skills such as alphabet recognition, phonemic awareness, and vocabulary development. Early educators make important instructional decisions in their classrooms about how to support these skills. Understanding these decisions, and the beliefs and experiences that contribute to them, is critical to informing improvement. This study explored the daily instructional decisions three Head Start teachers made about reading instruction. Specifically, we wanted to examine the relationships between Head Start teachers' professional, practical and personal experiences and their subsequent instructional choices about reading. Using a multiple case study design, classroom observations, questionnaire, and interview data suggested that teachers held strong beliefs about what constituted appropriate reading instruction. While professional knowledge played a limited role in informing these decisions, their abundant practical and personal knowledge was influential. Understanding teachers' beliefs about early reading can be an important first step in bringing about change in instructional practices.