Let's first of all get a clear understanding of what hypnotherapy is. Hypnotherapy is a complementary therapy. I will put this into one of three categories:
Conventional Medicine - Doctors, Surgeons, Consultants, Nursing Staff. Heavily regulated by the BMA in this country. The training to become a medic - including a psychiatrist - is very tough and again heavily regulated by government legislation. Medics have the legal right to diagnose disease and to prescribe drug therapy or other conventional treatments.
Alternative Medicine - offers diagnosis different to conventional medicine, examples are homeopathy, herbal medicine, acupuncture and traditional Chinese Medicine. Some of these are regulated by government legislation.
Complementary treatment - can be offered alongside conventional medicine - including hypnotherapy. Not regulated by government legislation - yes, that's right folks, not regulated. That means that anyone can advertise their services as a hypnotherapist with zero training, zero experience and zero understanding of the therapy if they so wish.
So, when you are searching for a hypnotherapist, remember that the profession has no legislation attached to it. Not all hypnotherapists are the same - in fact the training varies widely from very good practical and theoretical training at Diploma level right down to simple correspondence courses. And once trained, there is no probation period for new therapists. You could be the first ever client that your hypnotherapist treats when you go to visit them. If so, they should make you aware of their level of experience, and how many training hours they have had. If they don't, then ask...