Oxygen-ozone therapy is a complementary approach less known than homeopathy and acupuncture because it has come of age only three decades ago. This book clarifies that, in the often nebulous field of natural medicine, the biological bases of ozone therapy are totally in line with classic biochemical, physiological and pharmacological knowledge. Ozone is an oxidising molecule, a sort of superactive oxygen, which, by reacting with blood components, generates a number of chemical messengers responsible for activating crucial biological functions such as oxygen delivery, immune activation, release of hormones and induction of antioxidant enzymes, which is an exceptional property for correcting the chronic oxidative stress present in atherosclerosis, diabetes, infections and cancer. Moreover ozone therapy, by inducing nitric oxide synthase, may mobilize endogenous stem cells, which will promote regeneration of ischaemic tissues. The description of these phenomena offers the first comprehensive picture for understanding how ozone works and why, when properly used as a real drug within the therapeutic range, not only does not procure adverse effects but yields a feeling of wellness. Half of the book describes the value of ozone therapy in several diseases, particularly cutaneous infections and vascular diseases where ozone really behaves as a wonder drug. The book has been written for clinical researchers, physicians and ozonetherapists but also for the layman or the patient interested in this therapy.