CHIEF executive Andy Ambler says Millwall's board "will be planning for the next two or three years" during their annual end-of-season debrief.
The Lions' hierarchy, manager Neil Harris and key football staff are gathering at The Grove hotel in Hertfordshire, above, for three days of talks.
And following the club's relegation to League One, Ambler admits there has to be a fundamental change of approach at The Den – with an emphasis on long-term growth.
He said: "This week is about the future, moving forward and how we restructure. We will be planning for the next two or three years.
"What I will say about the past, and the chairman has said this as well, is that we've tended to take things year-by-year and focus on staying in the Championship.
"That's been difficult to do and some of our signings in recent years have been too short-term. We've got to change and go with a long-term strategy.
"Neil and Dave Livermore are crucial to that strategy, we've already restructured by bringing in a head of recruitment and we'll be advertising for a new U21s coach.
"That's a really important appointment because we need the right person to oversee our development squad, which is taking on a bigger emphasis.
"The aim is that when we come back to the Championship, we come back stronger."
The Lions will cut their cloth accordingly following the drop into League One, with the majority of the club's out-of-contract players expected to be released.
Harris said last week that he is already clear in his mind about who he wants to keep, and his retained list will be finalised over the coming days.
Asked about the financial impact of relegation, Ambler added: "Our income will drop by around £3million but Neil will have a competitive budget to work with.
"Our budget will probably be in the top three or four in League One. Last time we were in League One, we were top six budget-wise.
"John Berylson is committed to the club for the long-term and he's made that clear."