Illustrious (also known as "Illustrious Grand Master") is the seventh stage of a profession learned at the appropriate profession trainer. One must be at least level 75 to learn an Illustrious profession skill. One exception is where you can become Illustrious as soon as you can catch enough fish to level up to it.
Profession skill levels fall into eleven stages of increasing ability to learn and execute recipes: Apprentice, Journeyman, Expert, Artisan, Master (), Grand Master (), Illustrious (), Zen Master (), Draenor Master (), Legion Master (), and Kul Tiran / Zandalari Master ().
Change in Battle for Azeroth
- Non-expansion goes up to 300.
- Outland, Northrend, Cataclysm, and Pandaria progression bars each go up to 75.
- Draenor and Broken Isles go up to 100.
- Kul Tiras and Zandalar go up to 150.
- Not counting any racial or other bonuses, at a Grand Master skill level of 75  you can learn the Illustrious stage and gain up to a maximum of 75  points.
- Starting with Battle for Azeroth pre-patch, this proficiency range will have its own progress bar of 75 points.
- ^ a b Amanda Miller 2009-08-23. BlizzCon 2009 Insider Trader: Cataclysmic professions. WoW Insider.
- ^ a b Malgayne 2009-08-21. WoW: Cataclysm Recap. Wowhead News.
- ^ Battle for Azeroth Professions - Overview - (BfA) [Profession skill squish section]. WoW-Professions.com. Retrieved on 2018-09-26.
- ^ perculia 2018-07-09. Professions in Battle for Azeroth. Wowhead. (changelog)