The professional development of teachers continues to be a key initiative in educational reform. Callsforchangeemphasize theneed to stretch beyond theevent-driven examples of the past in favour of job-embedded approaches. This paper examines the role of school leadership in creating and supporting such change, and draws upon the informal testimony of practitioners to highlight the challenges for development of collaborative cultures of inquiry. Two key questions addressed were: to what extent and how did teachers change their views of theory assisted practice as a result of engaging in collaborative inquiry and what aspects of the school leadership role need to change in order to be successful in promoting collaborative inquiry? We support the view that there is a continuum of levels of understanding about the relationship between theory and practice, and we suggest that one way for leaders to support collaborative inquiry may be for them to become participant learners who contribute to a collective understanding of collaborative inquiry. Forming strong, collaborative cultures where teachers, principals, and college faculty study and learn together could provide the scaffold to support more meaningful educational reform.