This chapter describes hemiparesis followed by dementia using the case of a 73-year-old woman who presented to the emergency room with mild left hemiparesis since awakening the day before. Computed tomography (CT) scan showed a known old right parieto-temporal infarct and a right caudate nucleus lacune. Magnetic resonance imaging (MRI) done within 3 days of presentation show the same ischemic lesions without diffusion restriction, with mild leukoaraiosis and atrophy for age. Neuropsychological tests showed severe executive functions deficits, moderate to severe memory deficits, and mild visuoconstructive and ideomotor apraxia. The initial diagnostic impression was mixed dementia, although a purely vascular dementia could not be ruled out. Repeated mini-mental state examination (MMSE) showed decline over time, despite temporary improvement after initiation of a cholinesterase inhibitor, galantamine (Reminyl ER), 3 months after presentation. Blood pressure remained high during initial follow-up, requiring several anti-hypertensive medication adjustments.