Social work education in Britain has undergone repeated and fundamental restructuring for over a decade. Despite changes to practice and academic training requirements, there are some constants. One of these is the demand for social work students to demonstrate that they can �apply theory to practice� as part of qualifying requirements. This requirement, presented casually alongside a long list of further requirements, characteristically fails to grasp that understanding the relationship between theory and practice has long been a source of debate within social science. In many respects, the recent debate in Britain (see Trevillion, 2000) continues, and draws upon, consistent themes in social theory over the relative merits or otherwise of realist paradigms, with their underlying assumptions of a social world that can be revealed through the application of correct techniques. This historical intellectual legacy, together with a need for professional status dependent on a proper �knowledge-base�, drives demands that professional practice demonstrate the application of theory to practice. I want to suggest here that this demand betrays a lack of understanding of what theory is and what it can do and, at best, leaves students confused, whilst at worst it leads to cruel or ineffective practices in agencies. Here I outline the historical context that has led to a particular understanding of theory as a guide to action, point to some perils of its application in practice, and suggest a different method of dealing with theory on social work degree schemes.