Thomas Frank joined Brentford in December 2016, taking up the role of Assistant Head Coach alongside Richard O'Kelly.

The Danish coach spent nearly two decades in youth football, including time with Denmark's Under-16 and Under-17 teams. In 2013, he took up his first role in senior football as manager of Brondby IF in the Superliga. He coached them to top four finishes in successive seasons before leaving in March 2016.

Thomas was appointed Head Coach of The Bees in October 2018, shortly after Dean Smith left to join Aston Villa. He took the side to 11th in the table during his first year in charge. The following season he led the team to the Sky Bet Championship Play-Off Final.