Recent years have seen the development of novel neuroimaging techniques whose roles in the management of acute stroke are sometimes confusing and controversial. This may be attributable in part to a focus on establishing simplified algorithms and terminology that omit consideration of the basic pathophysiology of cerebral ischemia and, consequently, of the full potential for optimizing patients' care based upon their individual imaging findings. This review begins by discussing cerebral hemodynamic physiology and of the effects of hemodynamic disturbances upon the brain. Particular attention will be paid to the hemodynamic measurements and markers of tissue injury that are provided by common clinical imaging techniques, with the goal of enabling greater confidence and flexibility in understanding the potential uses of these techniques in various clinical roles, which will be discussed in the remainder of the review.