Chris Arnold joined Chipotle 15 years ago this month when the company was privately held and had fewer than 150 restaurants. In the intervening years, Chris helped position the company into a $12 billion publicly traded corporation that has more than 2,400 locations. Chris played offense with Chipotle’s “Food With Integrity” campaign, played defense with E.coli crisis communications challenges, and helped the company essentially redefine the quick-service restaurant (QSR) marketplace.

Chris has let friends know this week that he has made the decision to leave Chipotle on May 28, which is 15 years to the day he joined the company. Here’s wishing Chris the best of luck on whatever comes next.