REST is an acronym for restricted environmental stimulation therapy, a technique which examines human physiological and psychological reactions when a person is placed in surroundings free from stimuli such as noise, cold, movement, etc. This is the only volume offering systematic, controlled research on the newest technique of flotation REST, in which the patient floats in a water tank, as opposed to chamber REST (in a room). The clinical applications for treating conditions such as headache, hypertension and pain are discussed.