High teacher attrition rates hinder schools in their ability to provide quality instruction. This study seeks to understand why teachers leave early in their careers (within the first 5 years) using a mixed methods approach that combined 50 in-depth interviews with 15 public and 10 Catholic school teachers in the United States who left early with statistical analyses of public and Catholic school early leavers' responses in the national Schools and Staffing and Teacher Follow-up surveys. This study argues that to understand why teachers leave early requires examining teachers' entire experiences throughout their short time in the profession. A framework informed by sociocultural and commitment theories was developed through systematic analysis of the interview and survey data providing a complex approach for examining the phenomenon of early leaving. Findings suggest that teachers' career decisions were influenced by the unique public and Catholic school cultures, as well as their commitment to teaching, their teaching experiences, and their beliefs and values. Differences between public and Catholic early leaver experiences are discussed.