A range of evidential sources indicate that medical care was habitually provided in the various units of the Roman imperial army.* However, while there is no doubt that medical care was on offer within the Roman army, that it was provided by physicians who were also soldiers, and that it was supervised and managed by military commanders, its extent, raison d'être, formation, and impact on civic medicine are not beyond dispute.1 This chapter will evaluate the scope of medical care available to Roman soldiers during the High Empire and assess its impact on Roman healthcare in general, and upon popular medicine in particular. The essay's starting point will be an evaluation of the evidence in support of the existence of a 'medical corps', and its reach within the military setting. I will then move on to consider its responsibilities, and reconsider the influence of the Roman medical corps on wider society. Finally, to conclude, I will ask whether a 'grand design' lay behind the medical corps' foundation by the Roman imperial government.