Millwall manager Neil Harris has signed a new "long-term" contract with the Championship club.
The 40-year-old took over the Lions in March 2015 and guided the south London side to eighth place last season.
He led Millwall to promotion from League One in 2016-17 via the play-offs, having lost in the play-off final at Wembley the year before.
Assistant manager David Livermore and first-team coach Adam Barrett have also signed deals to remain at The Den.
"It's been a great experience and we've developed as a club consistently," said Harris, who scored 138 goals in two separate spells as a player with Millwall.
"What I want to do is keep growing with the club."
The club have not disclosed the length of his new deal.
Meanwhile, defender Byron Webster has signed a new one-year contract.
The 31-year-old has been with the Lions since 2014, but injury restricted him to just 12 appearances last season.