This decade witnessed a resurgence of interest in vascular dementia (VaD) as an increasingly important cause of senile dementia. Although definitions of dementia in general, and of VaD in particular, are still controversial recent diagnostic criteria for VaD acknowledge that pathogenetic mechanisms different from multi-infarct dementia are important in dementia causation. These include subcortical strokes, mainly lacunes, global hypoxic-ischemic events during acute stroke, and ischemic periventricular white matter lesions of the Binswanger type. These lesions tend to be manifested primarily by alterations of frontal executive function control. The importance of these ischemic vascular lesions in the clinical expression of Alzheimer's disease (AD) in very old subjects has also been recognized. Clinically, VaD may present in two forms: Acute VaD includes large-vessel infarction, and lacunar dementia due to small-vessel disease, including thalamic and caudate strokes. Subacute VaD includes Binswanger's disease (BD), cerebral angiopathy with leukoencephalopathy and CADASIL. The discovery of CADASIL, a genetic form of VaD mapped to chromosome 19 as a mutation of the Notch 3 gene, opened research avenues into the pathogenesis of BD. Finally, epidemiological evidence suggests that it may be possible to prevent VaD--and perhaps degenerative senile dementia--by controlling hypertension and other vascular risk factors. These findings offer hope for prevention of this growing public health problem.