After playing a vital role in helping to officially expand the College Football Playoff, Craig Thompson is calling it a career.

The Mountain West Conference commissioner and the longest-tenured active FBS commissioner announced on Wednesday he plans to step down on Dec. 31. Thompson was one of the four initial authors of the 12-team CFP proposal that was introduced, debated, tabled, and then ultimately adopted earlier this month.

“My one remaining priority was expansion of the College Football Playoff and viable access for the Mountain West,” said Thompson in a statement. “I take considerable pride in my committed engagement to this effort over the past two-and-a-half decades and look forward to the finalization of those details in the coming months. With CFP expansion accomplished and having invested almost a third of my life in the Mountain West, the time is now right for me to conclude my tenure and allow the conference to continue its momentum under new leadership.”

Thompson, 66, served as the Mountain West commissioner for 24 years.

He is also a member of the CFP’s management committee — composed of the 10 FBS commissioners and Notre Dame athletic director Jack Swarbrick. Thompson, Swarbrick, SEC commissioner Greg Sankey, and former Big 12 commissioner Bob Bowlsby wrote the 12-team proposal that will be put into place for the 2026 season, if not sooner.

With conference realignment chaos up and running again, it will be interesting to see how the MWC navigates the transition from one of the most experienced administrators in the sport to someone new.