Unsurprisingly, the name that they have chosen is Jones - the most common monicker in Wales. "At this stage the idea is still in the planning stages but it does have real potential," said a spokeswoman for the Wales Tourist Board, one of three groups behind the idea.
The event would form part of the board's "Homecoming" campaign which, with the slogan "It's time to come home", is promoting Wales to ex-pats and Welsh descendants around the globe, particularly in communities in Australia, New Zealand and Argentina.
At this stage the tourist board, the Welsh televisionchannel S4C and Cardiff Marketing have yet to secure a suitable location for the event. They are currently in discussion with officials at the recently completed 72,000-seater Millennium Stadium in Cardiff city centre.
"That would be the ideal venue for an event such as this," said a spokeswoman for the tourist board. "We are still trying to sort this out."
The organisers, who will also use the event to raise money for charity, are hoping to attract some of the most famous people named Jones ever to emerge from Wales, including the singer Tom and the actress Catherine Zeta. Other non-Welsh born namesakes of these celebrities such as the footballer Vinnie and the singer Grace would also be welcome, the organisers said.
Louise Wilson, of The Guinness Book of Records, said that there was currently no record for the largest gathering of people with the same surname under one roof. But she said: "There is a record for a family reunion held by the Busse family in America, where 2,369 of them came together."