How medical know-how progresses

► Advance of science is an important source of medical progress, but not only source. ► Important roles also played by advances in technologies, and learning in practice. ► The fact of multiple pathways has important policy implications. The conventional wisdom regarding the source of progress in medical practice highlights the role of basic scientific research into the nature of disease pathologies. This perspective neglects the important role of two other sources of progress in medicine. One is the advance of technologies that have enabled the development of new modalities of treatment and diagnosis. The other is learning in clinical practice. In many cases the advance of treatment has involved the interaction of all three of these pathways to progress.