Headache disorders are among the most common disorders of the nervous system. They are pandemic and, in many cases, they are recurrent and can accompany the patient for the whole life. These disorders impose a substantial burden on headache sufferers, on their families and on society: the individual impact is measured by the frequency and severity of attacks, while the societal burden is measured in terms of loss of activity at work and school as well as of costs for the health system. As a matter of facts, headaches are ranked in the top ten, and maybe the top five, causes of disability...