Orthostatic Hypotension (OH) is a common manifestation of blood pressure dysregulation. OH takes a heavy toll on quality of life. It has many potential etiologies, and many effects of aging can increase susceptibility to OH. Neurological disorders are especially likely to cause severe OH. In this brief review, the pathogenesis of OH is considered, particularly in terms of autonomic neuropathy, multiple system atrophy (MSA), pure autonomic failure, baroreflex failure, and dopamine beta hydroxylase deficiency. While OH is difficult to treat, its control greatly enhances the quality of life.