MRI has become far superior to other imaging modalities in the imaging of multiple sclerosis. It is also increasingly being used as a measure of disease activity when monitoring the efficacy of potential new treatments of MS. This new issue of Neuroimaging Clinics of North America covering Multiple Sclerosis has been divided into two volumes. The first volume covers the background of MS and the conventional MRI as it relates to MS. Some of the topics covered are:: Epidemiology, Pathology, and Conventional MRI. This new issue Guest Edited by Massimo Filipi is a must have clinical reference!