This article examines the effect involvement with professional development schools (PDSs) has had on the way colleges or universities prepare teachers, by following several partnerships that were begun in the mid-1980s, studied in 1990, and revisited in late 1995-1996. The article finds that the most dramatic changes in the school-based components of teacher education (field work or student teaching) took place in the early years, with more subtle refinements in the las' five years due to the maturation of the partnership relationship leading to greater understanding and colleague-ship between cooperating teachers and college supervisors. Changes in the campus-based components of teacher preparation are reported caused by increased roles of school-based faculty in teaching college courses and in giving feedback on courses and overall preparation programs, and by changes in the attitudes and approaches of campus-based faculty members. The article also looks at the degree to which these changes have been institutionalized and what factors have helped or hindered that process. It concludes by assessing these changes in light of the potential for PDS-type partnerships to provide for the "simultaneous renewal" of schools and of colleges or universities and by raising questions about the degree to which these changes, as important as they are, are impacting the core enterprise at each institution.