Investigation and treatment of patients suffering from autonomic circulatory failure should be based on the application of knowledge of basic physiology to the problem of a particular patient. For an overall evaluation of cardiovascular autonomic dysfunction, an analysis of the heart rate and blood pressure responses to standing usually is sufficient. Instruction in physical maneuvers such as squatting and leg crossing should be part of the treatment programs to reduce disabilities from orthostatic hypotension in patients with circulatory autonomic failure.