They say:
"Every Good Salon Guide salon is assessed using criteria which have been developed since 1991 following ongoing consultation with the general public and hairdressing industry.
Each of the four possible awards, Registered (R), 3, 4 or 5 star is based on training and qualifications so that when you visit a Good Salon Guide salon you can be assured that the stylists are qualified and/or suitably experienced, giving you confidence in the service they are performing.."