Teacher education reform in the United States (US) is a crucial part of a broader educational reform intended to improve teaching practice and, thus, student performance (Darling-Hammond, 2005). Teacher education reform has become an international trend (Bates, 2008; Garm & Karlsen, 2004), which in spite of the different national contexts and traditions, shares a set of similar expectations, foci, and even policy interventions (Loomis, Rodriguez, & Tillman, 2008). Underlying these reforms are the assumptions that the quality of teaching is the most important, if not the only, factor that contributes to changes in student learning, which is shaped by factors such as teacher salaries, working conditions, and public support for public schools (Education Policy White Paper Project, 2009). Teacher education is a major factor in improving teaching quality (Delandshere & Petrosky, 2004). Central to the quality of teaching are teachers' deep understanding of what they need to teach and the pedagogical practices that can be used to represent such understanding to students (D. L. Ball, 2000). These have become important foci for reform in teacher education programs in many countries. Policy initiatives to reform teacher education have been very similarly framed, inasmuch as governments have played important roles in establishing standards for what teachers need to know and do in their classrooms and in developing relevant assessments to regulate what students have learned and done (Tatto, 2006). However, when these surface-level similarities are analyzed more deeply, one uncovers competing forces with different expectations, foci, and approaches to teacher education reform (Cochran-Smith, 2001). Each of these approaches reflects different ideologies and appeals to different political interests, but none receives substantial empirical support (Apple, 2001; Cochran-Smith & Fries, 2001; Zeichner & Ndimande, 2008). Add to this that the contexts and cultural traditions of teaching and teacher education provide little opportunity for important teacher education reform initiatives and ideas to be realized (Feiman-Nemser & Floden, 1986; Little, 1990a, 1990b). Consequently, only an insightful and comprehensive understanding of these competing expectations, foci, and approaches to teacher education reform will have utility in informing future policy making and program development. The research community in teaching and teacher education must accept its notable and irreplaceable role in helping to develop such an understanding through an empirical base focused on the processes and outcomes of reform. In this issue of the Journal of Teacher Education (JTE), eight articles address reform and its complexities in the area of teacher education. In this editorial, we first highlight important arguments and findings that emerge from each article. Next, we challenge some of the authors' ideas with support from existing literature and suggest what further conceptual and empirical work is needed to understand dynamic and complex teacher education reform and its contexts. Reform With Competing Expectations for Learning Outcomes and Teaching Underlying various teacher education reforms are two related and seemingly irrefutable assumptions (Delandshere & Petrosky, 2004). First, the quality of teaching is the most important factor that influences student learning. Second, teacher education plays an important role in shaping quality teaching. However, these assumptions sometimes become conceptually ambiguous when used to guide the development of teacher education reform policy and programs. Theoretically speaking, student learning and quality teaching can be defined differently, depending on how one views society and education. Varying definitions imply a range of foci for teacher education reform. Following are three popular conceptions of student learning and teaching quality, as well as their respective foci for teacher education reform, which have made their way into various teacher education reform documents. …