Therrien led the Penguins to a 47-point improvement last season, guiding his team to a 47-24-11 record, the fourth largest single-season turnaround in NHL history. Therrien was a candidate for the Jack Adams Award as NHL coach of the year but lost out to Vancouver's Alain Vigneault.
Therrien's current deal was to expire after next season. He was promoted to head coach of the Penguins in December 2005 from the club's AHL affiliate in Wilkes-Barre/Scranton. He was also head coach of the Montreal Canadiens for parts of three seasons before joining the AHL Penguins.