Autoregulatory mechanisms exist to keep cerebral blood flow constant despite changes in blood pressure. Elevated blood pressure (acute and sustained) overwhelm these mechanisms resulting in extravasation of fluid and damage to cerebral blood vessels. The resulting thickening of the arterial wall with microaneurysmal formation predisposes individuals with sustained hypertension to various types of strokes. Studies in Nigeria and other parts of the world have shown that hypertension is a dominant risk factor for stroke, most especially the haemorrhagic type and its control is associated with reduced risk. This manuscript highlights the pathophysiologic mechanisms of hypertensive damage to cerebral blood vessels and its association with dementia.