There are 5 levels of Tai Chi Instructor in the UK these days:

1. Health-only Tai Chi Teacher
   - 5 years experience
   - these are the majority
   
2. Tai Chi Chuan Instructor
   - equivalent of 3rd dan black belt in any martial art
   - 5 years experience
   - these people are less common
   
3. Tai Chi Expert
   - 15 years experience
   - 10,000 hours tai chi chuan practice
   - 10 years teaching experience
   - fewer to be found
   
4. Tai Chi Master
   - 25 years experience
   - 30,000 hours tai chi chuan practice
   - 20 years teaching experience
   - pretty rare
   
5. Tai Chi Grandmaster
   - extremely rare

Peter Southwood has graded Sifu Waller as being a Tai Chi Expert based upon his practice quality and experience.