This study investigated the influences of prior life and employment history on the thinking and practice of beginning, second-career elementary and secondary school teachers. Data were drawn from classroom observations, journal writing, and open-ended informal interviews; case studies were then developed illustrating the impact of personal and professional experiences on career changers. Results suggest that personal and professional life histories of second-career teachers played a powerful part in the development of teaching practices. Experiences prior to becoming teachers influenced organizational and management structures set up in classrooms, expectations of and beliefs about children, ways in which curriculum was designed and instructional problems resolved, and views held of themselves as teachers. A task for teacher educators arising out of this study seems to rest in helping individuals recognize the relevance of personal explorations into their often well-established perspectives on teaching. Implications for teacher education include the need for developing programs which promote the kind of thinking necessary to assist career changers examine and utilize their previous life and career experiences to enhance classroom teaching. (LL)