There are three Classes for Exhibits to compete: Master Class, Professional Class and Novice. World titels can only be won in the Masters Class.
Best in World titles are only awarded in the main categories, not in sub-categories such as 1.a

Categories for the Master Class
Best In World Categories and their criteria.

1. Full-body exhibits of small/medium size huntable mammals
   1a. Full-body exhibits of small/medium size huntable mammals (up to/including roe deer)
   1b. Animal groups of small/medium size huntable mammals (up to/including deer)
2. Full-body exhibits of large huntable mammals
   2a. Full-body exhibits of large huntable mammals (larger than roe deer)
   2b. Animal groups of large huntable mammals (larger than roe deer)
3. Roe Deer head and shoulder exhibits
4. Head and shoulder exhibits other than roe deer
5. Winged game
   5a. Full-body exhibits of huntable birds
   5b. Full-body exhibits of animal groups of huntable birds
6. Small non-huntable birds (up to/including Seagull)
   6a. Full-body exhibits of small non-huntable birds
   6b. Full-body exhibits of small non-huntable bird groups
7. Large non-huntable birds (larger than Seagull)
   7a. Full-body exhibits of large non-huntable birds
   7b. Full-body exhibits of large non-huntable bird animal groups
8. Exhibits of small/medium size non-huntable mammals
   8a. Full-body exhibits of small/medium size non-huntable mammals
   8b. Full-body exhibits of small/medium size non-huntable mammal animal groups
9. Large non-huntable mammals
   9a. Full-body exhibits of large non-huntable mammals
   9b. Full-body exhibits of large non-huntable mammal animal groups
10. Mixed groups
11. Fish exhibits using the real skin (artificial heads and fins are allowed)
12. Skeletons
13. Reproductions (may include any traditional taxidermy reproduction)
14. Reptiles, amphibians (with skin)
15. Sculpting (live at the show)
16. Collective artists

Categories for the Professional and Novice classes:  

1. Full-body small huntable game exhibits (up to/including foxes)
2. Full-body large huntable game exhibits (larger than foxes)
3. Huntable birds
4. Huntable game head and shoulder exhibits
5. Deer head and shoulder exhibits
6. Huntable small game animal groups (up to/including fox/pheasant size)
7. Huntable large game animal groups (larger than foxes/pheasants)
8. Small mammals (up to/including badgers)
9. Medium-size mammals (larger than badgers up to/including deer)
10. Large mammals (larger than a deer)
11. Small birds (smaller than a pheasant)
12. Large birds (including pheasant size)
13. Animal groups of small non-huntable animals (larger animals up to the size of foxes or pheasants)
14. Animal groups of large non-huntable animals (animals larger than foxes or pheasants)
15. Full-body fish exhibits (with skin)
16. Fish groups (with skin)
17. Skeletons
18. Reproductions and models
19. Reptiles, amphibians (with skin)