Dynamic susceptibility MR perfusion imaging of the brain offers clinically relevant physiological data not obtainable by conventional MR imaging. As new treatments continue to be developed for stroke, neoplasm, dementia, psychiatric illness, headache, and trauma, the potential clinical applications of perfusion MR imaging in the diagnosis, triage, and therapeutic monitoring of these diseases will increase. MR perfusion techniques are likely to be at least as sensitive and specific as radionuclide-based techniques, and offer the added advantage of higher intrinsic resolution, convenient coregistration with conventional MR imaging, as well as, time and cost-effective imaging in patients for whom a routine MR imaging is obtained.