Currently there are increasing demands that teachers and other professionals become more reflective of both their practice and what it is that informs such practice. While such exhortations are many, there have been few studies of practical strategies to facilitate such reflection and even fewer investigations of the impact of various strategies upon the development of reflective practices. More important, there appears to be little, if any, evidence from the published literature that assisting professional workers to become reflective necessarily makes their practice more effective. This paper, after briefly reviewing some of the literature dealing with the definition and nature of reflection discusses some issues related to the question of 'What constitutes evidence of reflection?'. This question and the issues discussed have arisen within the context of a research programme being undertaken by the authors at the University of Sydney. The research programme is being supported by a Small Grant from the Australian Research Council. The research is an evaluation of the impact of strategies being used to promote reflective student teachers in a Bachelor of Education (Secondary) degree in the Faculty of Education (Smith, 1991 (a), (b) ).