Magnetic resonance spectroscopy (MRS) has been a fundamental and invaluable tool in the fields of chemistry and physics for over 40 years and has only been applied directly to the field of medicine in the last decade. MRS has contributed significant information on ischemic brain metabolism in the clinical patient. The potential of spectroscopy now extends to the diagnostic monitoring of metabolic change, in identifying markers of a therapeutic window, and establishing prognosis and outcome. This article presents a review of MRS studies of cerebral ischemia in clinical patients.