Orthostatic hypotension is a frequent pathology especially in older adults and inhospital patients. Prevalence is increasing with age, and is about 30 % of patients older than 65 years. Orthostatic hypotension is defined as a fall in blood pressure of at least 20 mmHg systolic or 10 mmHg diastolic when standing or during head-up tilt testing. Orthostatic hypotension is significantly associated with several adverse outcomes such as falls, neurodegenerative disease, cardiovascular outcomes (such as stroke or heart failure), and mortality. Different mechanisms may be involved in pathogeny especially medications. Etiological work up will evaluate cardiac response when standing. Neurogenic orthostatic hypotension is characterized by a cardiovascular autonomic failure due to central or peripheral nervous system disorders. Non-neurogenic orthostatic hypotension is primarily caused by hypovolemia. Therapeutic management is based on non-pharmacological therapies, especially legs venous compression, even if evidence for effectiveness is lacking. Pharmacological therapies may be necessary for neurogenic orthostatic hypotension.