The Head of Scientology will visit Dublin tomorrow to open a new centre for the religion.
The building in Firhouse will include a conference centre with room for 1,100 people, but the census shows there are just 87 scientologists in Ireland.
Former scientologist, Pete Griffiths, does not believe that figure is accurate.
He said: “I actually don’t think there is that many.
“I think some people just put that down as a joke, as people do sometimes on the census, they put down anything.”
No one knows yet what the building will actually be used for, and that is causing some concern among locals.
Local county councillors were invited to see the new building, with many saying they will not go and one telling the organisers that he did not want to go in alone.
One local councillor, Dermot Looney, said on Twitter that he will have nothing to do with them and that he will monitor the situation to make sure no vulnerable people are targetted.