There is a widespread view that clinical research is failing to advance appropriately, particularly in comparison with other aspects of biomedical science. I argue that this is due in part to an inadequate understanding of how medical advance occurs. The common usage of such terms as basic or fundamental, or the uncritical use of the term model is unhelpful—unhelpful, in that such terms tend to presuppose a certain model of clinical advance that is unusual, and furthermore, because they tend to exaggerate the importance of research in subjects such as biochemistry and genetics at the expense of other areas. I suggest that much medical research is best viewed as a form of engineering rather than science, and that the knowledge base and research funding for the amelioration of disease needs to be much more broadly based than at present.