Vascular dementia is a significant cause of intellectual and functional impairment in young patients consequent to cerebrovascular disease. Post-mortem studies show that VaD patients have a cholinergic deficiency like in Alzheimer's disease (AD). Cholinesterase inhibitors are now standard treatment for mild to moderate AD. This study aims to determine if donepezil, a cholinesterase inhibitor, would benefit patients with VaD by decreasing their scores in the VaDAS-cog and improvement in their CIBIC rating over a period of 24-weeks treatment. Adverse events will also be monitored.