Hypnotherapy is the use of hypnotism in treatment of ill health. It is most widely used in the treatment of stress realted conditions such as anxiety, asthma, migraine etc but is also widely used in changing habits and dependencies such as alcohol, tobacco and other drugs. Despite its bad press and controversial stage shows hypnotherapy when practised skilfully and responsibly has substantial medical and scientific credibility. It has been shown to reduce stress and for some people to be effective as a support in changing dependent behaviours.