Despite the enormous proliferation of literature on the nature and practice of reflection, still little is agreed about what it is, and that which is asserted is confusing and contradictory. Even the work of Donald Schon, which lies behind the debate on reflective practice in the professions, is problematic. Not only do SchOn's own ideas tend to lack practical application to social work and to have been superseded by later theorists, but the entire ctuvre to date leaves more questions than answers. Yet social work education has become steeped in demands that students should demonstrate reflection in practice as a teaming outcome. The danger this poses to vulnerable learners in the assessment relationship, when assessors' own conceptions of reflection may be poorly formed and may not match those of their students, is worryingly likely to compound the imbalance of power between them. It is arguable whether social work programmes should be assessing reflection at all. Until such time as we can state more clearly what it is, we may have to accept that there is no theory of reflection that can be adequately assessed.