The MR features of inflammatory lesions of the central nervous system are reviewed in this article, and the sensitivity and specificity of MR and CT in the detection of these lesions are compared. The advent of CT dramatically improved the morbidity and mortality of inflammatory disease by facilitating earlier and more accurate diagnosis which, in turn, produced more timely medical and surgical intervention. The efficacy of MR in the evaluation of inflammatory lesions must, therefore, be compared to CT in order to accurately asses its role.