John A. Ryle was Britain’s first professor of Social Medicine. In the 1930s and 1940s, at the peak of his influence, he was a vigorous proponent of social medicine, then a relatively new, if contested, field. This article examines Ryle’s views and activities under three broad headings: What was social medicine? What were Ryle’s politics? Why prioritise medical education? We conclude with the apparent failure of the social medicine project, at least as envisioned by Ryle.