Teachers' knowledge of the subjects they teach has been of enduring interest to governments, the profession and the wider society. In this book, Viv Ellis traces the development of three beginning teachers thinking about their subject knowledge in the context of Standards-based teacher education and the practice of auditing student teachers' subject knowledge. Ellis puts forward a theory of subject knowledge development that moves on from the objectivist and individualistic epistemologies associated with Standards and the practices of auditing to more a contextualist and sociocultural understanding of teachers' cognition and learning. An important implication of this study is that if teacher education wishes to have greater impact on the development of beginning teachers, teacher educators need to pay greater attention to the schools and subject department settings in which these beginning teachers learn.