The cranial computed tomograms of 29 patients with systemic lupus erythematosus (SLE) were reviewed. Twenty-two patients had a clinical course consistent with central nervous system involvement. Of these, 20 had abnormal CT studies during the course of their CNS symptoms. The most common finding was sulcal enlargement, either with or without ventricular enlargement, and it was prominent in patients with either psychosis or dementia. Infarcts and intracranial hemorrhages were seen as well. Seven CT studies were obtained in SLE patients without a clear diagnosis of CNS involvement. Only one of these was abnormal.