National Trainee Associations (NTA) in alphabetical order:
- Armenia
- Austria
- Azerbaijan
- Belgium
- Bulgaria
- Croatia
- Czech Republic
- Denmark
- Estonia
- Finland
- France
- Georgia
- Germany
- Greece
- Hungary
- Ireland
- Israel
- Italy
- Kosovo
- Latvia
- Lithuania
- Malta
- Moldova
- Netherlands
- North Macedonia
- Norway
- Poland
- Portugal
- Romania
- Russian Federation
- Serbia
- Slovakia
- Slovenia
- Spain
- Sweden
- Switzerland
- Turkey
- Ukraine
- United Kingdom of Great Britain