If you are a practicing Stage Hypnotist then law requires that you have adequate public liability insurance, and abide by the guidelines set out in the 1952 hypnotism act.

The stage hypnosis act 1952 is actually a pretty fair assessment and has been laid out to protect the public from humiliation and physical dangers.

However, the Stage Hypnosis Insurance that must be obtained is over the top and a total rip off. Because of the nature of stage hypnosis and how unpredictable it can be, nobody wants to insure a stage hypnotist. But there are several companies. See the link above to find out more.