The 1983 publication of "A Nation at Risk: The Imperative for Educational Reform" (National Commission of Excellence in Education) "initiated the longest sustained period of attention to public education in the nation's history and ignited a new wave of interest in teacher preparation" (NRC, Committee on the Study of Teacher Preparation Programs in the United States, 2010). Numerous reports on teacher education were initiated in response (Carnegie Forum on Education and the Economy, 1986; Holmes, 1990; Goodlad, 1990). According to the National Commission for Excellence in Teacher Education (1985), "…every part of a teacher's education--from the liberal arts programs of the prospective teacher to the continuing education of the veteran--can be improved; even the best exiting programs are not good enough." (p 1). These reports set the context for the Kansas State University (KSU) Professional Development School (PDS) Partnership. This paper will explore the foundations of the KSU PDS model designed in response to this urgent cry for reform in teacher education. The beliefs, purposes, and premises that formed the theoretical foundation for the initial PDS Partnership and have been practiced for 25 years are presented in this article.