Vascular dementia describes global cognitive decline attributed to the cumulative effects of ischemic vascular disease. Discrete and multiple cognitive skills, including memory, are successively lost as a result of focal cerebrovascular insults. Our understanding of vascular dementia has evolved over time, in part through our ability to neuroradiologically image changes in patients, and also through our increased understanding of the neuropsychologic organization of the brain. This paper reviews the development of our present understanding of vascular dementia, examines the status of "leukoaraiosis," pointing out current areas of controversy, and discusses clinical management.