This book represents the first serious attempt to explain the fundamental basis of ozonetherapy and is a relevant step towards achieving further progress. Ozone is now considered a real drug and, after reacting with body fluids, releases messengers and activates several mechanisms which are able to elicit multiple biological effects. The therapeutic window has been defined and, contrary to the dogma that 'ozone is toxic any way you deal with it', it has been shown that ozone toxicity can be tamed and even totally avoided. New powerful methodologies have been devised and astonishing clinical results in vascular and infectious diseases have already been achieved. An exciting novelty is the induction of an adaptive response that implies the unsuspected possibility of arresting cell degeneration due to endogenous chronic oxidative stress. However, further basic and controlled clinical studies need to be performed to fully exploit ozone's therapeutic potentials and to establish the real validity of this therapy. Authoritative scientists and clinicians should abandon their prejudice and consider the profound difference between endogenous oxidative stress and the new concept of ozonetherapeutic 'shock'. If this happens, we could soon have a simple and inexpensive tool to restore health in millions of patients. This book has been written in a plain scientific language and can be read by scientists and clinicians, as well as by patients keen on regaining a state of well being.