Anti Terror Combat has got three stages of graduation.
First one > white belt
Second one > brown belt
Third one > black belt
To join any of these ranks you have to do the following:
If you are already a martial artist and you have any rank which is recognized by the Anti Terror Combat organisation, you can get awarded.
For example: You are a green belt Karate, you will be awarded the white belt
For example: You are a 1. Dan Karate, you will be awarded the 1. Dan ATC
In both cases you must join the ATC organisation and you have one year time to proof, that you are familiar with the requirements of your grade awarded.
It only makes sense to join, if your martial arts background is more from a self defence sort rather than sportif only.
The other way to get any ATC rank is to join a school which provides the training and you learn the skills and become graduated.
That is what our latest rank Lawrence Shillingford (Dorset/UK) just did. He has shown all 23 required skills and is now a brown belt ATC.
Congratulations from headquarters!