Islanders have voted in favour of attempting what could become Scotland's biggest community purchase to date.
The estates cover South Uist, Eriskay and Benbecula
The 93,000-acre South Uist Estate in the Western Isles is owned by a syndicate which is offering to sell the land to local residents.
It takes in Eriskay and South Uist and a large part of Benbecula.
Community leaders said the ballot which secured a 70% majority to proceed with the purchase, was a "defining moment" in the area's history.
As well as 850 crofts, the estate includes fish farming operations, quarries and potentially lucrative shooting, mineral and fishing rights.
Talks have been taking place for more than a year between the estate's 3,000 residents and their landlords, a nine-family syndicate.
Concerns had been raised that land legislation reforms could allow the fragmentation of the area's interests by private ventures.
Steering group leader Angus MacMillan said the 70% support for proceeding with the buy-out plans represented a huge mandate.
Mr MacMillan told BBC Radio's Good Morning Scotland programme: "It is a massive vote in favour and I think it is a truly historical moment and a defining moment I hope, for the people of these islands.
"A community company will now be established, we required a mandate from the people to bring it to this stage and then to go on to the next stage.
"We hope that that work will start immediately."
Crofter and chartered accountant Calum MacMillan has returned to live and work on Uist.
The islanders will now elect a community company
He said: "There has never before been such an opportunity, this opportunity was given at the behest and with the good will of the current owners.
"Without their assistance and the way they see things moving, it would never have come this far."
Islanders will now elect representatives to the community company and enter into negotiations with Highlands and Islands Enterprise's community land unit and the Scottish Land Fund.
Angus McMillan acknowledged there may be some critics of the buy-out plans.
But the added: "I would just love to think what the people who have left these shores over the last 150 years would say if they were here today, I'm sure they would see this as a truly momentous occasion."