Hypertension is the most-prevalent modifiable risk factor for cardiovascular morbidity and mortality worldwide. Hypertension is highly prevalent among older adults (≥65 years), and aging of the population will substantially increase the prevalence of this condition. Age-related endothelial dysfunction and increased arterial stiffness contribute to the increased prevalence of hypertension, particularly systolic hypertension, among the elderly. The incidence of some forms of secondary hypertension also increases with age, mainly owing to the use of drugs (especially NSAIDs that have pressor effects) and the presence of chronic kidney disease, obstructive sleep apnea, and renal artery stenosis. Guidelines differ in thresholds and goals for antihypertensive drug therapy in the elderly because of a paucity of high-level evidence from randomized controlled trials and inconsistencies in the definition of 'elderly'. Medical treatment of hypertension reduces cardiovascular morbidity and mortality in the elderly, and all guidelines recommend lifestyle modifications and medical treatment for elderly patients whose blood pressure exceeds prescribed thresholds and who are at moderate or high cardiovascular disease risk. In the absence of comorbidities, which constitute 'compelling indications' for the use of specific antihypertensive drugs or drug classes, no clear evidence exists to support recommendations for the use of particular antihypertensive-drug classes in older adults.