Identifying the top 25 fashion illustrators alive today involves considering a range of factors including artistic innovation, influence on the industry, recognition, and contributions to the field. Here's a list of some of the most prominent fashion illustrators working today:

1. David Downton
2. Bil Donovan
3. Richard Haines
4. Tanya Ling
5. Gladys Perint Palmer
6. Mats Gustafson
7. Jason Brooks
8. Ruben Toledo
9. Julie Verhoeven
10. Piet Paris
11. Danny Roberts
12. Jean-Philippe Delhomme
13. Laura Laine
14. Megan Hess
15. Dallas Shaw
16. Hiroshi Tanabe
17. Marcel George
18. Garance Doré
19. Donald Robertson
20. Anja Kroencke
21. Blair Breitenstein
22. Jenny Walton
23. Sunny Gu
24. Shamekh Bluwi
25. Inslee Fariss

These illustrators have made significant contributions to the fashion industry through their unique styles, creative vision, and ability to capture the essence of fashion in their artwork. They continue to inspire and influence designers, brands, and aspiring artists around the world, solidifying their status as leading figures in the realm of fashion illustration.